LIBRARY OF CONGRESS. 

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UNITED STATES OF AMERICA. 



THE ESSENTIALS 



OF 



Medical Chemistry 



AND 



URINALYSIS. 



V BY 

SAM E. WOODY, A. M., M. D., 

Professor of Chemistry and Public Hygiene, and Clinical Lecturer on Diseases 
of Children, in the Kentucky School of Medicine. 






Secoud Editioit, 

(REVISED AND ENLARGED, WITH EIGHTY-FIVE ILLUSTRATIONS.) 






«APf. 5 1888 '- 



LOUISVILLE : 

John P. Morton & Co., Publishers. 

1888 






COPYRIGHTED BY 

JOHN P. MORTON AND COMPANY. 

1888 



PREFACE. 



The rapid exhaustion of the first edition has encouraged the 
author and publishers to present this, the second edition, revised, 
enlarged, and illustrated. As the name implies, the aim of the 
work is to present the essential facts of a course of lectures on 
Medical Chemistry and Urinalysis, so that the student need not 
wade through the more exhaustive text -books. The author 
claims no originality for the facts, but has appropriated any 
thing of service wherever found. The selection of material and 
the plan of presentation is the outgrowth of his experience as 
a general practitioner and as a teacher of Medical Chemistry 
for the past ten years. The subjects treated are so numerous 
that the descriptions are as brief as is consistent with clearness, 
but the principles of the science and the application of the 
facts to medicine have been stated more fully. The writer hopes 
the book may prove useful to medical students, for whom it was 
designed, and that his labor may lessen theirs. 

1506 W. Walnut Street. Louisville. 



THE ESSENTIALS OF 



MEDICAL CHEMISTRY. 



INTRODUCTION. 

" Chemistry is that branch of science which treats of the com- 
position of substances, their changes in composition, and the laws 
governing such changes." (Webster.) 

The distinctive characteristic of chemical action is change 
in composition. A bar of soft iron is the same in composition 
whether it be hot or cold, luminous or non-luminous, magnetized 
or unmagnetized. But when it undergoes chemical action a sub- 
stance is formed which, though it contains iron, is en- 
tirely different from it in composition and properties.* 
Matter is that of which the sensible universe is 
composed. It is indestructible. Although we may 
cause matter to assume a variety of forms, and ren- 
der it under certain conditions invisible, yet in none 
of these changes is the smallest particle destroyed. f 
When carbon is burned in an atmosphere of 
oxygen it disappears, and, so far as we can learn by 
the senses of sight and touch, it is lost ; but the result 
l of this burning is an invisible gas, whose weight is 
equal to that of the carbon which has disappeared, 
plus the weight of the oxygen required to burn it.J 




Fig. 1. 



* Experiment. Heat pieces of platinum and magnesiuni wire. Note that 
while the platinum is unaltered, the magnesium burns and is converted into a 
white powder of magnesium oxide. 

t Experiment. Weigh a small porcelain crucible containing powdered 
iron. Heat it, and when combustion is complete, weigh again and note the 
increase in weight, and also that a new substance is formed, which, though it 
contains iron, is not iron. 

J Experiment. Burn charcoal in a jar of oxygen or air. (Fig. 1.) Add 
lime-water and agitate. Note the white precipitate of carbonate of lime. 

B (5) 



b INTRODUCTION. 

All matter has weight. Apparent weight is that which we 
determine by balances in the open air. The absolute weight of 
a body is its weight in vacuo. 

By the specific weight or specific gravity of a substance we mean 
its weight as compared to that of some other substance taken 
as a standard. The standard for solids and liquids is water; for 
gases, air or hydrogen. 

Matter exists in one of three states, solid, liquid, or gaseous. 
In the solid state the particles are held together so rigidly as to 
give the body a definite shape; while in the liquid state the at- 
traction is so slight as to allow the particles to move freely upon 
each other and the body to take the shape of the vessel that con- 
tains it. In the gaseous state the mutual attraction of the par- 
ticles is entirely overcome, and their distance from each other 
depends upon the pressure to which the gas is subjected. The 
term fluid is applied to any thing capable of flowing, whether 
liquid or gaseous. It is highly probable that all substances, 
which are not decomposed by heat or cold, are capable of exist- 
ing in all three states. Heat is absorbed and cold produced 
wherever the particles are to be driven farther apart, as in the 
passage of a substance from the solid to the liquid or from the 
liquid to the gaseous state. 

When the two solids ice and common salt are mixed, they 
form a liquid, and great cold is produced.* Perspiration in evap- 
orating assumes the gaseous state, and absorbs in the change 
enough heat to keep the body at its normal temperature in spite 
of the hottest weather. f 

On the other hand, when a substance passes from a rarer to a 
denser state it gives out again the heat absorbed in its passage 
in the opposite direction. 

If we examine the infinite variety of substances upon our 
earth we find most of them are compounds, i. e. they can be de- 
composed into two or more other substances, distinct in their 
properties from the substance from which they were derived and 

* Experiment. Fold tin foil into the shape of a little dish ; add powdered 
if:e and salt. Spill water on the table and set the dish in it. Note how quickly 
it is frozen fast to the table. 

t Experiment. Put a little water in a similar dish. Against the sides and 
bottom throw a spray of ether. Note that the evaporation *of the ether is so 
rapid that the water is quickly frozen. 



INTRODUCTION. 7 

from each other. There are some substances which have never 
been decomposed. These are called elements. Only seventy ele- 
ments are at present known; but, as our methods of investigation 
improve, this number may be increased by the discovery of other 
elements, or decreased by decomposing some of those now con- 
sidered elements. Only about one half of these enter into the 
materia medica, and will be noticed in this work. 

Table of Elementary Bodies, with Their Symbols and 
Atomic Weights. 



Name. 



Aluminium 

Antimony (Stibium)... 

Arsenic 

Barium 

Beryllium 

Bismuth 

Boron 

Bromine 

Cadmium 

Caesium 

Calcium 

Carbon 

Cerium 

Chlorine 

Chromium , 

Cobalt 

Copper (Cuprum) 

Didymium 

Erbium 

Fluorine 

Gallium 

Germanium 

Gold (Aurum) 

Hydrogen 

Indium 

Iodine 

Iridium •. 

Iron (Ferrum) 

Lanthanum 

Lead (Plumbum) 

Lithium 

Magnesium 

Manganese 

M EEC u r Y (Hydra rg y • 

rum) 

Molybdenum 



1 

Symbol 


Atomic 
Weight. 


Al 


27 


Sb 


122 


As 


75 


Ba 


137 


Be 


0.4 


Bi 


210 


B 


11 


Bi- 


80 


Cd 


112 


Cs 


133 


Ca 


40 


C 


12 


Ce 


141 


CI 


35.5 


Cr 


.32.2 ' 


Co 


58.8 


Cu 


63.4 


D 


145 


E 


168 


F 


19 


Ga 


70 


Ge 


163 


Au 


197 


H 


1 


In 


113.4 


1 


127 


Ir 


198 


Fe 


56 


La 


139 


Pb 


207 


Li 


7 


Mg 


24 


Mn 


55 


Hg 


200 


Mo 


96 



Name. 



i Symbol 



Nickel 


Ni 


Niobium 


Nb 


Nitrogen 


N 


Norwegium 


Ng 


Osmium 


of 


Oxygen 

Palladium 




Pd 


Phosphorus 


p 


Platinum 

Potassium (Kaliumj... 
Rhodium 


Pt 
K 
Rh 


Rubidium 


Rb 


Ruthenium.. 

Samarium 


Ru 

Sm 


Scandium 


Sc 


Selen ium 


Se 


Silicon 


Si 


SlLVEB (Argentum 

Sodi cm (Natrium) 

Strontium 

Sulphur 


Ag 

Na 
Sr 

S 


Tantalum 


Ta 


Tellurium 


Te 


Thallium 


Tl 


Thorinum 


Th 


Tin (Stannum) 


Sn 


Titanium 


Ti 


Tungsten, or Wolfram 
Uralium 


w 

Ul 


Uranium 


u 


Vanadium 


v 


Ytterbium 


Yb 


Yttrium 


Y 


Zinc 


Zn 


Zirconium 


Zr 



Atomic 
Weight. 



58.8 

94 

14 
214 
200 

16 
106.6 

31 
197.4 
39.1 
104.4 

85.4 
104.4 
150 

44 

79.4 

28 
108 

23 

87.6 

32 
182 
128 
204 
235 
118 

50 
184 
187 
240 

51.2 
173 

92 

65.2 

89.6 



To explain the laws governing chemical phenomena we adopt 
the old atomic theory * 



* Deinocritus, 460 b. a, said : " The atoms are invisible by reason of their 
smallness — indivisible by reason of their solidity; impenetrable and unalter- 
able." 



8 INTRODUCTION. 

We will take up the theories and laws, not in the order of their 
enunciation, but of their natural sequence. 

It is assumed that matter is composed ultimately of infinitely 
small particles called atoms; that each element is composed of 
atoms, all of a certain size, weight, etc. Atoms do not exist alone, 
but in groups called molecules. In an element the molecule is 
composed of pairs of atoms of the same kind ; in compounds they 
consist of two or more atoms of different kinds. It has been de- 
termined that equal volumes of all substances in the gaseous state, 
and under like conditions, contain the same number of molecules. 
So a gallon of hydrogen gas and one of oxygen gas containing the 
same number of molecules, and those molecules consisting of 
pairs of atoms, must contain the same number of atoms. Fur- 
thermore, it is found that the gallon of oxygen is sixteen times 
as heavy as the gallon of hydrogen. So each oxygen atom must 
also be sixteen times as heavy as the hydrogen atom. Hydrogen 
being the lightest substance known, its atomic weight is taken as 1, 
and consequently the atomic weight of oxygen is 16. The atomic 
weights of other elements are determined in a similar way. By 
" atomic weight" is not meant the absolute weight of atoms (for 
that is not known), but the weight of the atom as compared to 
the hydrogen atom. The atomic weight of carbon is 12. If car- 
bon combines with oxygen, atom for atom, the new substance 
(CO) resulting from that action will consist of molecules, in each 
of which the carbon will weigh 12 and the oxygen 16, and, as the 
whole mass is composed of these molecules, the same proportion 
obtains throughout the new compound. So 12 is found to be the 
combining weight of carbon, and 16 of oxygen. If, however, the 
combination should occur in the proportion of one atom of carbon 
to two atoms of oxygen, then each molecule must consist of 12 
by weight of carbon to 32 of oxygen, and that must be the pro- 
portion throughout the entire substance. 

Between these two compounds no intermediate one can occur, 
for the carbon atom must take one or two, or more, oxygen atoms. 
It can not take a fraction of one, for atoms are indivisible. 
Hence, we deduce the following Law : Substances combine in cer- 
tain fixed proportions (atomic weights), or in multiples of these pro- 
portions. 

Symbols are abbreviations of the names of the elements. They 



INTRODUCTION. 9 

consist of the initial letter of the Latin name ; but if the names 
of several elements begin with the same letter, the single-letter 
symbol is reserved for the most common element, and for the 
others another letter is added. Thus, we have nine elements 
whose names begin with C ; the most common is carbon, whose 
symbol is C ; the others add other letters, as chlorine, CI ; cobalt, 
Co; copper (cuprum), Cu, etc. The symbol indicates just one 
atom. When more than one atom is to be represented, the num- 
ber is written just after and below the symbol, thus, C 4 . 

Formulae are to molecules what symbols are to elements. They 
indicate the kind and number of atoms composing the molecule. 
When more than one molecule is to be indicated, the number 
is placed in front of the formula, thus, 5H 2 0. A parenthesis 
inclosing several symbols or formulae should be treated as a single 
symbol, thus, 2(NH 4 ) 2 C03=N 4 Hi6C 2 06. 

An equation is a combination of formulae and algebraic signs 
to indicate a chemical reaction and its results. As no matter is 
ever lost or created in a reaction, the number of each kind of 
atoms before the equality sign must be the same as after it. 



INORGANIC CHEMISTRY. 



Classification of the Elements. The elements are usu- 
ally divided into two great classes: (a) Metals, about fifty-five in 
number, possessing a peculiar luster, good conductors of heat and 
electricity, and whose oxides when combined with water form 
bases ; (b) Non-metals, about fifteen in number, possessing little 
luster, poor conductors of heat and electricity, and whose oxides 
combine with water to form acids. A better classification, and 
the one we shall adopt, is the following, based upon chemical 
properties : 

The Non-metallic Elements. 

I. The Hydrogen and Oxygen Group. 

II. The Chlorine Group : Fluorine, Chlorine, Bromine, Iodine. 

III. The Sulphur Group: (Oxygen) Sulphur, Selenium, Tellu- 
rium. 

IV. The Nitrogen Group: Nitrogen, Phosphorus, Arsenic, An- 
timony, Bismuth. 

V. Boron. 

VI. The Carbon Group : Carbon, Silicon. 

The Metals. 
I. The Alkaline Group : Lithium, Ammonium, Sodium, 
Potassium, Rubidium, and Csesium. 

II. The Alkaline Earths Group : Magnesium, Calcium, Stron- 
tium, Barium. 

III. The Earths Group: Aluminium, Lanthanum, Cerium, 
Didymium. 

IV. The Zinc Group : Zinc, Cadmium. 

V. The Iron Group: Chromium, Manganese, Iron, Cobalt, 
Nickel. 

VI. The Lead Group : Tin, Lead. 

VII. The Copper Group : Copper, Mercury. 
VIII. The Silver Group: Silver, Gold, Platinum. 



INORGANIC CHEMISTRY. 



11 




Fig. 2. 



THE NON-METALS. 

I. Hydrogen and Oxygen Group. In a strict arrangement 
hydrogen would be placed in Group I of the metals and oxygen 
in the sulphur group. But we will consider them in a group 
to themselves, because (a) of all the elements hydrogen is taken 
as the standard for atomic weights, combining weights, valence, 
etc. ; (b) oxygen plays a most 
important role in chemistry, 
and its deportment with the 
other elements forms the basis 
of our classification ; (c) the 
chemistry of these two will 
best serve as an introduction 
to the study of the other ele- 
ments. 

Hydrogen (H — 1) occurs 
free in volcanoes, gas - wells, 
etc. ; combined in water and 
all organized 3 bodies. All acids 
are salts of hydrogen. Prepared in various ways from its com- 
pounds, the most convenient being to displace it from sulphuric 
acid by zinc, thus, 

H2S0 4 -Zn=ZnS0 4 -H 2 . (Fig. 2.) 
Physical Properties. Transparent, colorless, 
odorless, tasteless gas ; the lightest substance 
known, fourteen and a half times as light as 
air; hence used in balloons. Long suspected 
to be a metal, because it displaces metals in 
chemical compounds, forms alloys with cer- 
tain metals, and conducts electricity. This 
was proved in 1S77, when Pictet condensed it 
under great cold and enormous pressure into 
a bluish metallic liquid. 
Chemical Properties. Hydrogen does not support ordinary com- 
bustion or animal respiration. It burns in air with a pale but 

Experiment. By means of a wire gauze spoon hold some sodium beneath 
the water and under a cylinder. The hydrogen gas liberated by the sodium 
from the water will rise in bubbles, fill the cylinder, and displace the water. 




12 



INORGANIC CHEMISTRY. 



very hot flame. *f With pure oxygen it forms the oxyhydrogen 
flame. This is the hottest flame known, and a stick of lime held 

in it glows with dazzling 
brilliancy,forming the cal- 
cium or Drummond light. 
Mixed with air or oxygen, 
it explodes violently on 
contact with a spark. J 

Oxygen (0 — 16). 
Sources. Most abundant 
of the elements, compris- 
ing one fifth. of the air, 




Fig. 4. 



eight ninths of water, one half of the crust of the earth, and three 
fourths of all organized bodies. Prepared most easily by heating 
potassium chlorate (Fig. 5): 
KCIO3-KCI+O3. 
If manganese diox- 
ide (Mn0 2 ) be mixed 
with the chlorate, the 
gas is liberated more 
quietly and at a lower 
temperature. The man- 
ganese dioxide is unal- 
tered in the reaction. 
It seems to act by its 
mere presence, an in- 
fluence called catalysis. 
Physical Properties. 
Gas; liquefied (Pictet, 
1877) by great cold and 
intense pressure ; colorless, odorless, tasteless; 1.10 times as heavy 

^'•.Experiment. If an inverted jar of the gas is suddenly turned up, and a 
flame held a foot or two above, the gas escaping from the jar rises rapidly, and 
in coming in contact with the flame burns with a slight explosion. 

f Experiment. If a jar of the gas be held mouth down and a candle be 
passed up into it (Fig. 3), the gas ignites and burns quietly at the open end, 
while the candle passed up into the gas is extinguished, but may be relighted 
again by the burning gas as it is withdrawn. 

I Experiment. Fill a bladder or rubber bag with two parts of hydrogen 
and one of oxygen or five of air. Attach a tube and blow up soap bubbles in a 
basin. (Fig. 4.) Touched with a flame, they explode. 




INORGANIC CHEMISTRY. 



13 



Fig. 6. 



as air. Water dissolves only three volumes to the hundred, but 
enough to sustain aquatic life. 

Chemical Properties. Intense affinities ; combines with e very- 
element except fluorine. The product of its action is called an 
oxide, and the process oxidation. Oxidation so rapid as to 
produce heat and light is called combustion; if no light, 
slow combustion. Substances that burn in air burn more 
brilliantly in oxygen,* and many substances that do not 
burn in air will burn in this gas.f By this property oxy- 
gen is usually recognized and distinguished from most 
other gases. Oxygen, especially in its diluted form (air), 
is the great supporter of combustion, for which its abun- 
dance and universal presence eminently 
fit it. Combustible and supporter of com- 
bustion are only relative terms. When a^ 
combustible substance burns in 
porter of combustion the union 
tual, one being as much a 
party to the action as the 
other. A jet of air J or ox- 
ygen burns as readily in 
coal gas as a jet of coal 
gas burns in air or oxygen. 
: The one in greatest abun- j 
dance is usually called the 
supporter of combustion. 
Oxidizing agents are compounds in which oxygen is held so feebly 
it is readily given up to substances Jaaving greater affinity for it. 

Uses. The process of respiration is a species of combustion, 
and, as oxygen is the best supporter of combustion, it is. the best 




Fig. ' 




"Experiment. A bit of phosphorus, dried by pressing between folds of 
blotting paper, is placed in a combustion spoon (Fig. 6), ignited, and lowered 
into a jar of oxygen. (Fig. 7.) The combustion is so intense that the phos- 
phorus volatilizes, and its vapor burns throughout the jar with a brilliancy so 
dazzling that it is called the " phosphorus sun." 

t Experiment. A watch-spring is wound into a spiral, tipped with a bit 
of tinder or a piece of yarn dipped in sulphur. This is lighted and lowered into 
a jar of oxygen. (Fig. 8.) The iron catches fire and burns with brilliant scintil- 
lations, globules of melted iron falling and melting into the glass, unless the 
bottom be covered with sand or water. 

J Experiment. Secure an ordinary lamp chimney (Fig. 9) and a wide cork 



14 



INORGANIC CHEMISTRY. 



(and only) supporter of animal respiration. Administered in cap- 
illary bronchitis, oedema glottidis, etc., when the patient can not 
take in a volume of air sufficient to supply the 
requisite amount of oxygen. 

Ozone. If through a portion of air or oxy- 
gen electric sparks be passed,* a part of the ox- 
ygen will acquire a pungent odor and peculiar 
properties. The same change may be induced 
by various chemical processes, e. g. by mixing 
permanganate of potassium and sulphuric acid, 
or when phosphorus partially covered with 
water is 




n.....fe^T— :: -- 




exposed 
to the 
air. This 
modi- 
fied ox- 
ygen is 
called 
ozone. It 

is one Fig. 10. 

and a half times as heavy as ordinary oxygen, for its molecule 

contains three instead of two atoms. Very energetic, oxidizing 

to fit its lower end. Pass through the cork a narrow tube (c) connected by rub- 
ber hose with the house gas, and a wider one opening into the air. Turn on the 
coal gas and light it as it issues from the tube (c). The cork with the flame (not 
too large) is then inserted into the chimney, where it continues to bum, suffi- 
cient air entering through the wide tube (a). Upon turning on more gas the air 
is crowded out and the chimney filled with coal gas. The gas flame disappears 
from the tube (c), and an air flame appears upon the tube (a) as the entering 
air burns in the atmosphere of coal gas. The excess of coal gas may also be 
lighted as it escapes, showing a gas flame above and an air flame within the 
chimney. On lessening the flow of gas the air will again be in excess, and the 
flame again appear on the narrow tube (c.) In the gas flame above the lamp 
chimney (Fig. 9) heat some potassium chlorate in a combustion spoon until it 
melts and oxygen begins to bubble up. Then lower it into the atmosphere of 
coal gas within the chimney. The escaping oxygen burns brilliantly, the coal 
gas being the supporter of the combustion. 

*Siemens's apparatus for ozoning oxygen (Fig. 10) consists of two tubes, the 
inner surface of the inner and the outer surface of the outer tube being coated 
with tin-foil, and each connected with the poles of an induction coil or Toepler- 
Holtz machine. A current of oxygen passing between these tubes may be ozon 
ized to the extent of fifteen or twenty per cent. 



INORGANIC CHEMISTRY. 



15 




substances unaffected by ordinary oxygen. Oxidizes potassium 
iodide with liberation of iodine, hence its test: paper dipped in a 
solution of potassium iodide and starch is colored blue in the 
presence of ozone. * Ozone is found in the air, especially after 
thunder-storms, and when present in considerable amount (as- 
much as .00005 per cent) is apt to irritate the 
respiratory tract ; but by oxidizing infecting 
germs, etc., it prevents the spread of infec- 
tious diseases. 

Compounds of Hydrogen with Oxy- 
gen. Two are known — hydrogen oxide, or 
water, H 2 ; hydrogen peroxide, or oxygen- 
ated water, H 2 2 . 

Water /(H2O) occurs widely distributed 
in nature ; an important constituent of all 
organized tissues ; forms seven eighths of the 
human body. * li? - Um 

Physical Properties. Transparent, colorless, odorless, tasteless — 
liquid. Below 32° F. (0° C.) it is a solid (ice), and above 212° 
F. (100° C.) a vapor (steam or water gas). In solidifying, water 
expands ; so ice floats. The boiling point is higher than 212° F. 
under increased pressure or when it contains solid matter in solu- 
tion. 

Water is the greatest of all solvents. The watery solution of 
a fixed substance is called a "liquor" and of a volatile substance 
an "aqua" 

One body is said to dissolve in another when they coalesce 
and their particles intimately mingle. This is possible only in 
the liquid and gaseous states. When a substance dissolves it 
takes on the physical state of the solvent, e. g. a solid or gas dis- 
solving in water becomes a liquid and then mixes with the water, 
the gas elevating the temperature and the solid lowering it. 
Heat assisting the liquefaction of a solid, and opposing that of a 
gas, hastens the solution of the one and retards that of the other. 
Most solid substances when separating from a solution take with 

"Experiment. Pour a little ether into a beaker, across the top of which 
is a glass rod supporting a strip of blue litmus paper and one of paper dipped 
in potassium iodide and starch-water. Hold a hot glass rod in the jar (Fig. 11) ; 
the ether will undergo slow combustion, producing acid fumes which redden 
the litmus, and ozone which blues the other paper. 



16 



INORGANIC CHEMISTRY. 




them, as a necessary part of the crystal, a certain definite amount 
of water — water of crystallization. This water does not modify the 
chemical nature of the substance, but is necessary for maintain- 
ing the crystalline form. If 
the crystal loses its water of 
crystallization by heat or ex- 
posure, it effloresces into an 
amorphous powder. Some sub- 
stances when exposed absorb 
water from the air and deli- 
quesce (melt down). 

Chemical Properties. The 
chemical composition of water 
may be proved by (synthesis) 
combining its constituents 
(H 2 +0=H 2 0) (Fig. 12), or by 

Fig. 12. Water from burning H. ( ana l ysis) passing the ga l va nic 

current through water until it is decomposed into its component 
gases (H 2 0=H 2 +0). (Fig. 13.) Neutral in reaction ; combines 
with the oxides of the metals to form hy- 
drates (bases), and with the oxides of the 
non-metals to form acids. 

Natural waters are never pure. The na- 
ture of the impurities in water depends on 
the condition of the atmosphere through 
which it has fallen as rain, and the nature 
of the geological strata through or over 
which it has passed, for water dissolves 
something from almost every thing it 
touches. Good, potable (drinkable) wa- 
ter should be cool, clear, and odorless 
It should contain just enough dissolved 
gases and solids to give it an agreeable 
taste, neither flat, salty, nor sweetish; 
and should dissolve soap without form- 
ing a curd. Water impregnated with inorganic matters, especially 
salts of calcium, is called hard. A much more serious contam- 
ination is with organic (animal and vegetable) matters. Such 
water is a prolific source of disease. It is probable, in fact almost 




Fig. 13. 



INORGANIC CHEMISTRY. 



17 



proven, that most infectious diseases are due to micro-organisms, 
many of which find the nio>t favorable conditions for their life 
and growth in water contaminated with organic, especially ani- 
mal, matter. Though chemical analysis can not detect the dis- 
ease-producing elements, it can detect organic impurity, without 
which they can not exi:*t. This is easily done thus: (1) Half fill 
a clean bottle with the water, warm, agitate, and critically smell 
it. A foul odor indicates organic impurity. (2) Fill a clean pint 
bottle three fourths full, add a teaspoonful of the purest white 
sugar: set aside in a warm place for two days, when, if it becomes 
cloudy, it is unlit to use. These rough-and-ready tests are those 
best suited to the 
practitioner, the 
more exact meth- 
ods being practi- 
cable only to the 
chemist. 

To purify nat- 
ural waters, they 
may be boiled to 
kill living organ- 
isms, and filtered 
to remove a u s- Fl ?- 14 - 

pended matters ; but for chemical purposes, where great purity is 
desired, they are distilled* (aqua de*tiUata,Y . 8. P.}. 

Mineral waters are those possessing special therapeutic value. 
They may be classed as follows : 

1. Carbonated ', those charged with carbonic acid. 

2. Sulphur, containing H 2 S or some soluble sulphide. 

3. Alkaline, containing alkaline salts of potassium, sodium, or 
lithium. 

4. Saline, containing neutral salts. 

5. Chalybeate, containing iron. 

6. Thermal* or hot waters. 

-When a liquid is rapidly vaporized, and the vapor, passing over into a 
colder vessel, is reeondensed. the process is called distillation. (Fig. 14.) If a 
solid be similarly treated it is called sublimation. When water containing solid 
matter in solution is distilled, the solids remain in the vessel, while the water 
passes over, enabling us to obtain perfectly pure water. "When a mixture of 
two or more liquids is heated, the one having the lowest boiling point distills 
first, leaving the others behind. This is called fractional distillation. 




18 INORGANIC CHEMTSTRY. 

Hydrogen Dioxide — Oxygenated Water (H 2 2 ). Prepared 
most easily diluted by passing C0 2 through water holding barium 
dioxide in suspension. 

Ba0 2 +C0 2 +H 2 0--==BaC0 3 +H 2 2 . 
The BaC0 3 may be allowed to subside and the clear solution 
poured off. 

Properties. When concentrated it is a colorless, syrupy liquid, 
with a pungent odor and taste — prone to decompose into H 2 0+O. 

Used to bleach* the hair and skin, converting brunettes into 
blondes ; as a disinfectant to ulcers, ozoena, and in diphtheria, 
especially when the membrane has invaded the nose; also as a 
test for pus in urine, with which it causes an effervescence. 

RADICALS. Every molecule is composed of two parts, called 
radicals, held together by chemical affinity. Both radicals may be 
elements, as in (H) — (CI), or one may be elementary and the other 
compound, as (H) — (N0 3 ), or both compound, as (NH 4 )— (N0 3 ). 
.Some compound radicals can be isolated, e. g. by heat, (Hg) — (CN) 
= Hg + CN. Others decompose whenever set free. Whenever 
2i galvanic current is passed through a compound, the chemical 
.affinity is overcome by the electricity, and the molecule separates 
into its two radicals, one of which goes to the positive and the 
other to the negative pole. Unlike electrical conditions attract, 
so the radical going to the negative pole must be electro-positive, 
and the one going to the positive pole electro-negative. The me- 
tallic radicals are usually electro-positive and the non-metallic 
electro-negative. 

Some radicals are more intensely electro-negative or electro- 
positive than others. In the following list the more common 
elements are so arranged that each is usually positive to those 
following it and negative to those preceding : 
Positive end: +K, Na, Mg, Zn, Fe, Al, Pb, Sn, Bi, Cu, Ag, Hg, 
Pt, Au, H, Sb, As, C, P, S, N, I, Br, CI, F, O — Negative end. 

A radical is electro-positive or electro-negative only in its rela- 
tion to other radicals ; for, while C is positive to O, it is negative to K. 

* Experiment. Secure an old oil painting darkened with age, or take 
paper dipped in lead acetate and blackened by hydrogen sulphide : wash it 
with hydrogen dioxide, and the dark stain will be made white by the lead sul- 
phide being oxidized into sulphate. 



INORGANIC CHEMISTRY. 19 

In formulae the electro-positive radical is written first and the 
electro-negative next. 

The greater the difference between the electrical condition of 
two radicals, the greater the energy with which they unite and 
the more stable the product, and, vice versa; e. g. O has a strong 
affinity for K, a weak one for CI, and will not unite with F under 
any circumstances. An idea once prevailed that the relations of 
affinities were fixed and constant between the same substances, 
and great pains were taken to construct tables similar to the 
above to show what was called the " precedence of chemical affin- 
ities." These tables showed the order of affinities for the circum- 
stances under which the experiments were made, and nothing else. 

The circumstances attending chemical reactions are so com- 
plicated that in the greater number of cases it is impossible to 
predict the precedence of affinities and the result of an untried 
experiment. 

Among these modifying causes may be mentioned : 

1. Temperature, changes of which often reverse chemical affin- 
ities. Moderately heated, mercury and oxygen will readily com- 
bine, but when highly heated their affinity is destroyed, and they 
will refuse to unite, or, if already combined, will separate. 

Ordinarily free carbon has no affinity for oxygen, but at high 
temperatures it surpasses all other elements in its greediness for 
that substance, even taking it from a metal so extremely electro- 
positive as potassium. 

2. Volatility. Whenever in a mixture of two or more substances 
it is 2)ossible, by a rearrangement of the radicals, to form a compound 
volatile at the temperature of the experiment, such rearrangement will 
occur and the volatile compound be formed. For example : 

(Fe) (S)+(H 2 ) (S0 4 )=(Fe) (S0 4 )+(H 2 ) (S) ; or, 

2 (NH 4 ) (Cl)+(Ca) (C0 3 )=(lS T H4) 2 C03+(Ca) (Cl 2 ) ; or, 

H3BO3+3 Na Cl=3 H Cl+Na 3 B0 3 . 

3. Insolubility. Whenever, on mixing two or more substances in 
solution, it is possible, by rearrangement of the radicals, to form an 

Experiment. Into the vessel shown in Fig. 13 pnt some water; add solu- 
tions of red litmus, potassium iodide, and boiled starch ; connect with the gal- 
vanic battery. The electric current decomposes the potassium iodide into iodine, 
which gathers at the positive pole, producing a blue color, with the starch, and 
potassium at the negative, where it produces alkali, turning the red litmus blue. 



20 INORGANIC CHEMISTRY. 

insoluble compound, that rearrangement will occur and the insoluble 
compound be formed as a precipitate. For example : 

(Ca) (Cl 2 )-j-(NH 4 ) 2 (00 3 )=(Oa) (C0 3 )+2 (NH 4 ) (CI). 
It is especially important to remember this law, for its applica- 
tion in tests, incompatibilities, and antidotes. 

4. Nascent State. Ordinarily the atoms of an element are 
grouped in pairs, and hence somewhat indifferent to the attrac- 
tions of other atoms; but just as they are being liberated (born) 
from a compound they are alone. Each atom, having no fellow, 
readily enters into combination with any atom it meets. This 
state is called nascent (nasci, to be born). 

5. Catalysis. This is the name given to the unexplained influ- 
ence exerted by some substances of inducing chemical reactions 
between other substances without itself undergoing any change. 

The valence of a radical is its combining value, or its value in 
exchange for other radicals.* Here again hydrogen is taken as 
the standard. A radical that combines with or takes the place 
of one atom of hydrogen is said to be univalent (one valued) ; of 
two atoms, bivalent; three, trivalenl; four, quadrivalent; five, quin- 
quivalent; six, sexivalent. The valence is indicated by a Roman 
numeral just above and after the radical, thus : (NH4 1 ), Ca 11 , 
(P0 4 )in SiiV AsV svi. The two radicals of every saturated 
compound must possess an equal number of unsatisfied valences. 
Hence, 

In HC1 the radical CI is equivalent to 1 atom of hydrogen j 1 

In H 2 the radical O is equivalent to 2 atoms of hydrogen ; 

In NH 3 the radical N is equivalent to 3 atoms of hydrogen ; 

In CH 4 the radical C is equivalent to 4 atoms of hydrogen. 
Therefore CI is univalent, bivalent, N trivalent, and C quadri- 
valent. 

The same regard for valence is observed when radicals are 
made to displace each other, thus : Hi 2 (S0 4 ) n requires two atoms 
of Ki or one of Znii to form Ki 2 (S0 4 ) n or Znii(S0 4 )n 

Some elements exercise more than one valence : e. g. mercury 
may be univalent, as in Hgl, or bivalent, as in Hgl 2 ; or iron may 
be bivalent, as in FeCl 2 , or the double atom (Fe 2 ) sexivalent, as 
in Fe 2 Cl6. The termination "ous" is given to those compounds 

* The student should bear in mind that valence has nothing to do with the 
combining weight or the chemical activity of an element. 



INORGANIC CHEMISTRY. 



21 



in which the positive element exercises its lower valence, and 
"ic" to those in which the higher valence is exercised, as, FeCl 2 , 
ferrous chloride ; and Fe 2 Cl6, ferric chloride. 

In the following table the most commonly occurring simple 
or elementary radicals are arranged according to their valence : 

Table of Valence. 



I 


II. 


in 


IV 


V 


VI 


F, CI 


Ba, Sr 

Ca,Mg 

Cd, Zn 




Al 


C, Si 






Br, I 


Au 


Pt 






H,Ag 


Bo 


















K,Na 


Pb,Sn 




Pb, Sn... 






(NHA Li.. 


S, Se 








S,Se 
Fe 2 Cr 2 




Fe, Cr 










Mn, Co.... 








Mn^ Coo 




Ni 








Ni 2 






N, P 




N, P... 








Bi,Sb,As. 




Bi, Sb, As 




Cu,Hg 


Cu, Hg.... 







The next table shows the valences, together with the symbols 
and formulae, of the most common electro-negative (acidulous) 
radicals : 

CI is the negative radical of all chlorides. 

Br is the negative radical of all bromides. 

I is the negative radical of all iodides. 

CN is the negative radical of all cyanides. 

HO is the negative radical of all hydrates. 

N0 3 is the negative radical of all nitrates. 

CIO3 is the negative radical of all chlorates. 

C 2 H 3 2 is the negative radical of all acetates. 

O is the negative radical of all oxides. 

S is the negative radical of all sulphides. 

50 3 is the negative radical of all sulphites. 

50 4 is the negative radical of all sulphates. 
C0 3 is the negative radical of all carbonates. 
C 2 4 is the negative radical of all oxalates. 

. C4H4O6 is the negative radical of all tartrates. 
1 1 \ C 6H 5 7 is the negative radical of all citrates. 
1 1 -j P0 4 is the negative radical of all phosphates. 
c 5 [ B( ^3 is the negative radical of all borates. 

c 



22 



INORGANIC CHEMISTRY. 



The student should learn these tables thoroughly, for with 
them he can easily know the formula of all the principal inor- 
ganic and organic compounds. 

II. The Chlorine Group. 

Name. Derivation of Name. Symbol. At. Wt. 

Fluorine Fluor spar F 19 

Chlorine x^pk 1 green CI 35.5 

Bromine Rptifiog, stink Br 80 

Iodine I66qg, violet I 127 

The members of this group are all univalent and much alike 
in their sources and physical and chemical properties. They 

differ in degree rather 
than in kind, forming 
.a graded series. Hence 
we will consider them 
all together. 

Sources. Never free 
in nature. The princi- 
pal source of fluorine is 
fluor spar (CaF 2 ), while 
compounds of chlorine" 
bromine, and iodine are 
abundant in sea and 
other salt waters. 

Preparation. Fluor- 
ine has probably never 
been isolated ; the oth- 
ers may be prepared 
by removing the hydrogen from their hydrogen salts (hydracids) 
by means of oxygen derived from manganese dioxide, thus: 
4HCl+Mn0 2 =MnCl 2 +2H 2 + Cl 2 .* 
4HBr+Mn0 2 =MnBr 2 +2H 2 0+Br 2 . 
4HI+Mn0 2 =MnI 2 +2H 2 0+I 2 . 
Physical Properties. Fluorine is not known in the free state, 

^Experiment. Into a flask standing in a cup of sand over a heater (Fig. 
15) pour several ounces of hydrochloric acid and half as much black oxide of 
manganese, and agitate. The gas passes out through the wash bottle, and, being 
heavier than air, collects in the tall cylinder, where its yellowish -green color 
makes it visible. 




Fig. 15. 



INORGANIC CHEMISTRY. 



26 



but probably a colorless gas. Chlorine is a very irritating yellow- 
ish-green gas, two and a half times as heavy as air, slightly soluble 
in water (three volumes), forming "Aqua chlori, U. S." Bromine 
is a red liquid, giving off red vapors of a disagreeable, irritating 
odor; very slightly soluble in water. 

Iodine is a solid, in bluish-gray scales, which, when warmed, 
give off violet vapors ; insoluble in water except by the interven- 
tion of an alkaline iodide ; * soluble 
in alcohol ; irritating, even caustic. 

Chemical Properties. Intensely elec- 
tro-negative ; great affinity for the 
metals,j especially hydrogen. J In 
negativeness, and consequently in af- 
finity for the metals, F is greatest, CI 
next, Br next, and I least. Therefore, 
in compounds with the metals, F will 
^ displace CI, and CI will displace Br, 
HlP^ and either F, CI, or Br will displace L§ 
Fig. 16. These elements destroy coloring mat- 
ters and noxious effluvia in two ways: (1) by abstracting their 
hydrogen ; (2) by abstracting the hydrogen of water, setting free 
nascent oxygen, which oxidizes the matters in question. || 





Fisr. 17. 



* Experiment. To some water in a test-tube add a few scales of iodine ; it 
does not dissolve. Now add a crystal of potassium iodide; it dissolves easily. 

t Experiment. Into a jar of chlorine introduce some copper or bronze 
foil, or sprinkle some powdered antimony. They inflame spontaneously. 

X Experiment, (a) Into a jar of chlorine lower a lighted candle. (Fig. 16.) 
The hydrogen of the tallow burns in the chlorine to form hydrochloric acid, 
and all the carbon is liberated as smoke. (5) Into a similar jar thrust a piece 
of paper dipped in warm turpentine. It inflames spontaneously and burns, 
evolving dense clouds of smoke. 

I Experiment. Take two large test-tubes half full of water. Into one put 
a grain of potassium bromide, into the other potassium iodide: add chlorine- 
water to each. The chlorine will liberate the bromine in one and the iodine 
in the other. This may be shown (a) by their color; (b) by adding a few drops 
of carbon bisulphide or chloroform, which on agitation will gather all the free 
bromine and iodine, and be colored brown with the one and violet with the 
other; (c) add a few drops of starch-water, which will give brown with bromine 
and a deep blue with iodine. 

II Experiment, (a) Into one bottle of chlorine gas introduce a piece of 
dry calico, into another a moist piece. The moist calico is rapidly bleached, 
while the dry is but slowly affected. (&) To a solution of indigo, cochineal, or 
some aniline color add chlorine-water. It is immediatelv decolorized. 



24 



INORGANIC CHEMISTRY. 



Medical. Chlorine gas and bromine vapor are used for disin- 
fection. Inhaled they cause severe coryza and bronchitis. Taken 
into the stomach, bromine and iodine cause gastro-enteritis. The 
antidote is boiled starch. Locally bromine is used as an eschar- 
otic and iodine as a counter-irritant. 

Pharmaceutical. The following preparations are officinal: 
Tinctura Iodi (§j-Oj); and Liquor Iodi Compositus (Lugol's Solu- 
tion) (Iodine gvi, potassium iodide § iss, and water Oj). The 
so-called colorless tincture of iodine is made by adding ammonia- 




Fig. 18. Commercial Preparation of HOI." 
water to the tincture until it is decolorized by converting the 
iodine into ammonium iodide. 

Tests. In the free state chlorine and bromine may be known 
by their bleaching, color, odor, etc. Iodine is recognized by the 
blue color it strikes with starch. 

Acids. All acids have, as their (positive) basylous radical, 
hydrogen, which may be replaced by metals to form salts. They 
may generally be recognized by a sour taste and the property of 
turning vegetable blues (e. g. litmus or purple cabbage) to reds. 
Acids whose acidulous (negative) radicals contain oxygen are 



INORGANIC CHEMISTRY. 



25 



called oxacids; those containing no oxygen, hydracids. The mem- 
bers of the chlorine group form both classes of acids. 

The hydracids of the chlorine group are as follows : 

H+F=HF— Hydrogen Fluoride — Hydrofluoric acid. 

H+C1=HC1 — Hydrogen Chloride — Hydrochloric (muriatic) 
acid. 

H+Bi— HBr — Hydrogen Bromide — Hydrobromic acid. 

H+I=HI — Hydrogen Iodide — Hydriodic acid. 

Binary compounds — i. e. those of only two elements — are named 
by calling first the name of the positive and then that of the neg- 
ative radical, affixing to the latter the termination "ide" 




Prepared by treating the appropriate salt with H 2 SG 4 , thus: 

CaF 2 -fH 2 S04=CaS0 4 +2HF. 

2NaCl+H 2 S0 4 =Na 2 S0 4 +2HCl.* 

2KBr+H 2 S(V=K 2 S0 4 +2HBr. 

2KI+H 2 S0 4 =K 2 S0 4 +2HI. 

Physical Properties. Colorless, irritating gases ; sharp, sour 

taste; very soluble, water dissolving several hundred times its 

.own volume, forming aquae known by the simple name of the acid 



"Experiment. To prepare hydrochloric acid in the laboratory, put sev- 
eral ounees of common salt and about twice as much sulphuric acid into a flask 
fitted as shown in Fig. 1\\ Hydrochloric acid gas is disengaged and may be col- 
lected by displacement (like chlorine. Fig. 18). or over mercury. The solution 
of the gas (the ordinary form i is obtained bypassing the gas through a series 
of Wolff bottles (as shown in the figure) containing cold water. 



26 



INORGANIC CHEMISTRY. 



itself, thus : The so-called hydrochloric acid is a solution of the 
hydrochloric acid gas in water.* 

Chemical Properties. Strong acids; true acids even without 
water. 

Uses. HF attacks silicon energetically, hence is used to etch 

glass ; very poisonous, and 
burns made by it heal with 
difficulty. 

HCl is very useful in 
the arts. Aqua regia, or 
nitro- muriatic acid, is a 
mixture of nitric and hy- 
drochloric acids. It is the 
only solvent of gold and 
platinum. The metals are 
attacked by the nascent 
chlorine evolved by the 
oxidation of the H of the 
In medicine HCl is often prescribed 




Fig. 20. 



HCl by the O of the HN0 3 
as a tonic. 

HBr, like all bromides, is a sedative. HI, 
like all iodides, is an alterative. 

Tests. Fluoride+H 2 S0 4 — etches glass.f 

Chloride+AgN0 3 — white precipitate, solu- 
ble in ammonia. 

Bromide -f-AgNOs — yellowish- white precip- 
itate, slightly soluble in ammonia. Fig. 21. 

Iodide +AgISr03 — yellow precipitate, insoluble in ammonia. 

If to a bromide or iodide some chlorine-water and starch paste 




* Experiment. Fill two cylinders, one with hydrogen, the other with 
chlorine. Apply them mouth to mouth, and agitate until the gases are mixed. 
Hold their mouths to a flame (Fig. 20), or expose to direct sunlight. They ex- 
plode with a shrill report, and are filled with hydrochloric acid fumes. Invert 
one cylinder over water; the gas is absorbed and the water rises to take its 
place. Into the other thrust a piece of moist blue litmus; it is reddened. 

t Experiment. On a plate of glass coated with wax or copper- plate var- 
nish (six parts of mastic, one of asphalt, and one of wax dissolved in turpentine) 
draw a design with a pointed instrument. Invert over a lead dish supported as 
in Fig. 21, and warmed gently. Hydrofluoric acid gas is evolved aud attacks 
the glass wherever the wax has been scratched off. Upon removing the wax 
the design is found permanently etched on the glass. 



INORGANIC CHEMISTRY. 



27 




Fig. 22. 



be added, the bromine and iodine will be liberated, the bromine 
striking a brown and the latter a blue color with the starch. 

Oxacids are formed by oxides of non-metals combining with 
water. The elements of the chlorine group, being very negative, 
have but little affinity for oxygen. 
Iodine has most, bromine less, chlo- 
rine still less, and fluorine will not 
unite with oxygen at all. 

Chlorine, bromine, and iodine 
each forms a series of oxides per- 
fectly analogous, so we will notice 
only those of one — chlorine. 

The several oxides are distinguished by prefixes derived from 
the Greek numerals indicating the number 
of oxygen atoms in the formula, thus: 
C1 2 — Chlorine Monoxide. 
C1 2 2 (?)— Chlorine Dioxide. 
CI2O3— Chlorine Trioxide. 
CLO4— Chlorine Tetroxide. 
CI2O5 — Chlorine Pentoxide. 
CI2O7 — Chlorine Heptoxide. 
These oxides combining with water form 
the corresponding acids, thus: 
C1 2 0+H 2 0=2HC10— Hydrogen Hypochlorite— Hypochlorous 
acid. 

C1 2 3 +H 2 = 2 HC10 2 — Hydrogen Chlorite— Chlorous acid. 
Cl 2 5 -fH 2 — 2 HCIO3 — Hydrogen Chlorate— Chloric acid. 
C1 2 7 +H 2 = 2 HCIO4 — Hydrogen Perchlorate — Perchloric 
acid. 

Note. — The names of oxacids are derived from the negative element other than 
oxygen, and to this certain affixes and prefixes arc added to indicate the degree of 
oxidation. The one containing more oxygen has the affix u -te, M less oxygen, "-ous." 
If there is in the same scries another acid with more oxygen than the " -ic," it is given 
the prefix ''per- ;" if less than the " -otis," the prefix " hypo-" (under). Acids ending 
in "-ic" form salts ending in "-ate;" those ending in i, -otzs'' farm salts ending in 
"-ite." The foregoing chlorine acids illustrate this. 

All these oxides, as well as their corresponding acids, are 
easily decomposed, sometimes with explosion ; * hence much used 




Fig, : 



* Experiment. Their oxidizing- action on combustibles may be shown by: 
(a) Mix together a dram each of powdered potassium chlorate and sugar; place 
on a brick (Fig. 22) and touch off with a glass rod dipped in sulphuric acid. A 



28 



INORGANIC CHEMISTRY. 



as oxidizing agents and as explosive mixtures.* The most im- 
portant of these salts is potassium chlorate, used in medicine and 
in the laboratory for the sake of its oxygen. 

III. Sulphur Group. 

Sulphur .....S 32 

Selenium Se 79.4 

Tellurium Te 128 

The elements comprising this group are solid at ordinary 
temperatures; bivalent and sexivalent; possess electro-negative 




Fig. 24. 

affinities which, as in other groups, decrease as the atomic weights 
increase; form hydracids as well as oxacids. 



vigorous combustion occurs. (5) Drop some crystals of potassium chlorate into 
a conical glass of water (Fig. 23) ; add several bits of phosphorus; then by means 
of a pipette introduce sulphuric acid at the bottom of the glass. The phospho- 
rus takes fire and burns at the expense of the oxygen of the potassium chlorate. 
"Experiment. Mix on a sheet of paper a scruple of powdered potassium 
chlorate and five grains of some combustible powder, as sulphur, antimony 
sulphide, or tannin. Wrap it up in the paper, place upon an anvil, and strike . 
with a hammer. It explodes violently. 



INORGANIC CHEMISTRY. 



29 



The analogy between their compounds is shown in the fol- 
lowing table: 

Hydro-ic Hypo-ous 

acid. Dioxide. Trioxide. acid. -ons acid. -ic acid. 

H 2 S S0 2 S0 3 H 2 S0 2 H 2 S0 3 H 2 S0 4 . 

H 2 Se Se0 2 Se0 3 H 2 Se6 3 HSe0 4 . 

H 2 Te Te0 2 Te0 3 H 2 Te0 3 H 2 Te0 4 . 

Selenium and Tellurium are of no medical interest, and will 
will not be further noticed. 

Sulphur occurs free, especially in the neighborhood of volca- 
noes ; occurs combined as sulphides and sulphates in many val- 
uable ores, and in small 
quantity in the animal 
and vegetable kingdoms. 

Preparation. The na- 
tive sulphur freed from 
stones is refined by dis- 
tillation, as shown in Fig. 
24. The crude sulphur is 
melted in the tank by the 
hot draft from the fire be- 
low, and then runs down 
through a pipe into the 
retort, where it is. vapor- 
ized. This vapor entering 
a large brick chamber, is 
condensed in fine, feath- 
ery crystals, called flower 
of sulphur or sublimed sul- 
phur .* If the chamber 
be hot, it condenses into 
a liquid, which is drawn 
off and molded into rolls, 
called roll brimstone. Sublimed sulphur is apt to contain more 
or less acid, and is washed (sulphur loturn). Boiled with lime and 
precipitated with HC1, it forms sulphur precipitation, U. S. P. This 
mixed with water is milk of sulphur (lac sulphuris, U. S. P.) 

"Experiment. Some .sulphur is heated in a small retort or flask con- 
nected with the side tubulure of a large receiver. (Fig. 25.) The vapor passes 
into the receiver, where it condenses" in flowers of sulphur. 




Fig. 25 



30 



INORGANIC CHEMISTRY. 



Physical Properties. A brittle yellow solid ; insoluble in water, 
hence tasteless, etc. 

Chemical Properties. Inflammable, hence called "brimstone" 
(burn-stone). Combines with metals, forming sulphides.* Sul- 
phur forms compounds remarka- 
bly analogous to those of oxygen, 
e.g.: 

H 2 0. KHO. C0 2 . H 2 C0 3 . HCNO. 
H 2 S. KHS. CS 2 . H 2 CS 3 . HCNS. 
Uses. In the arts, to make gun- 
power, matches, etc. ; in medicine, 
as a laxative, parasiticide, and al- 
terative. We have only theoretical 
explanations of the method of its 
absorption; but that it is absorbed 
is certain, for persons taking it ex- 
crete enough to blacken silver car- 
5jjij§ ried on the person. 

Hydrogen Sulphide — H 2 S — 
Hydrosulphuric Acid or Sulphureted 
Hydrogen — occurs in sewer gas and 
other effluvia from decomposing 
organic (especially animal) matters, and in the water of sulphur 
springs. 

Prepared in laboratory by decomposing a sulphide, thus: 

FeS+H 2 S0 4 ==FeS0 4 +H 2 S. 
Physical Properties. Colorless gas, having the odor of rotten 
eggs or intestinal flatus; slightly soluble in water. 

Chemical Properties. Very feeble acid; burns with pale blue 

flame : H 2 S+0 3 ==S0 2 +H 2 0.f 




Fig. 26. 



"Experiment. In a small glass flask, the neck broken off, a little sulphur 
is heated to boiling. If now a bundle of line copper wire or a piece of sodium, 
in a combustion spoon, be previously heated and then lowered into the vapor 
(Fig. 26), it burns brilliantly. 

Experiment, Mix in a dish equal parts of iron filings and flowers of 
sulphur; moisten with water and set aside. Within a half hour it gets hot, 
vaporizes the water, and is converted into a black mass of PeS. 

t Experiment. Burn the gas from a jet; (a) Hold near the flame a. glass 
rod dipped in ammonia; white crystals of ammonium sulphide are formed. 
(6] Hold a cold, dry bell glass over the flame; it is bedewed with water. 



INORGANIC CHEMISTRY. 



31 



Forms characteristic precipitates with most metallic salts, hence 
a valuable test reagent.- 

Tests. The presence of H 2 S even in minute quantities may be 
detected by its odor, and by its blackening paper moistened with 
a solution of lead acetate. 

Physiological. When inhaled H 2 S is an active poison, com- 
bining with the hemaglobulin and destroying its oxygen-carrying 
power. Even when highly diluted, as in the at- 
mosphere of city dwellings, clumsily "fitted with 
the modern conveniences," it produces a low feb- 




Fig. 27. 

rile condition. When concentrated, or even moderately diluted, 
the gas proves rapidly fatal. 

Treatment. Fresh air, artificial respiration, and stimulation. 

Carbon Disulphide— CS 2 . Obtained by bringing S into con- 
tact with heated charcoal. A colorless, volatile liquid of a fetid 
odor, unless it is very pure. A valuable solvent for S, P, india- 
rubber, etc. 

Sulphur Oxides and Acids. 

Dioxide — S0 2 +H 2 0=H 2 S0 3 — Sulphurous acid. 
Trioxide— S0 3 -H 2 0=H 2 S0 4 — Sulphuric acid. 



"Experiment. To show the action of H 2 s on metallic salts, connect sev- 
eral wash bottles with the generator A. as shown in Fig. 27. the last tube ending 
in a beaker of ammonia-water. A dilute solution of lead acetate is put in B. of 
tartar emetic (antimony) in C. of arsenic in D. of zinc sulphate in E. The gas in 
passing precipitates lead sulphide (black) in B. antimonions snlphide (orange i 
in C. arsenions snlphide (yellow) in D. zinc sulphide (white' in E. and is finally 
taken np by the ammonia to form ammonium snlphide. 



32 



INORGANIC CHEMISTRY. 



Sulphur Dioxide — S0 2 occurs whenever sulphur or any of 
its compounds are burned in air or oxygen. 

Prepared in laboratory by decomposing sulphuric acid by 
copper or charcoal, thus: 

2H 2 S04+Cu=CuS0 4 +2H 2 0-fS0 2 . 
2H 2 S0 4 +C=2S0 2 +C0 2 +2H 2 0. 

Physical Properties. A colorless gas, with a suffocating odor 
(of burning matches); dissolves in water to form sulphurous acid 
(H 2 S0 3 ). . 

Chemical Properties. Neither burns nor supports combustion ; 
a strong deoxidizer; by removing O 
from coloring matters and infecting 
germs it bleaches* and disinfects. 

Uses. Sulphur dioxide, sulphur- 
ous acid, and the sulphites possess 
the property of destroying micro-or- 
ganisms and arresting fermentations. 
A sulphite digested with sulphur 
forms a hyposulphite, thus : 

Na 2 S0 3 +S=Na 2 S 2 3 . 
Sodium hyposulphite has the same 
uses as the sulphites, and is also a 
valuable solvent of the silver salts 
in photography. 

Sulphur Trioxide — S0 3 . Made by oxidizing S0 2 in the 
manufacture of sulphuric acid, This is done upon a large scale 
by passing S0 2 from burning sulphur into a chamber kept filled 
with vapor of nitric acid, steam, and air.f The nitric acid gives 
up a part of its oxygen to oxidize a portion of the S0 2 to S0 3 . 
2HN0 3 + 3S0 2 =3S0 3 +H 2 0+N 2 2 . 




Fig. 28. 



"Experiment. Some sulphur is ignited beneath a tripod on which fresh 
flowers are placed, and the whole covered by a bell glass. (Fig. 28.) The flowers 
are bleached. The color may be restored by washing with some dilute alkali or 
acid that will combine with or displace the S0 2 , or with very dilute nitric acid, 
which will restore the oxygen removed by the 80 2 . 

fThe manufacture of sulphuric acid may be illustrated on the lecture-table 
by the apparatus shown in Fig. 29. The lead chamber is represented by a large 
Mask. Into this are led (a) X 2 () 2 from the two-necked bottle on the right; (b) 
SG 2 from a mixture of sulphur and manganese dioxide in the flask to the left; 
(c) steam from the other flask, and (<2) air or oxygen through the rubber tube. 



INORGANIC CHEMISTRY. 



33 



The S0 3 then combines with the water thus produced (S0 3 -f- 
H 2 0=H 2 S0 4 ), and more water is supplied by a jet of steam 
thrown constantly into the chamber. 

The N2O2 has the power of taking up oxygen from the air and 
becoming N 2 4 , ' 

N 2 02 + 02=^20 4 , 

which in turn parts with this oxygen to oxidize a new quantity 

N2O4+2 S0 2 =N 2 2 + 2 S0 3 . 
Thus the process is kept up as long as the S0 2 , air, steam, and 




N2O2 are supplied. The acid condenses with the water upon the 
floor of the chamber, and is drawn off, concentrated, and sold as 

Sulphuric Acid— H 2 S0 4 — " Oil of Vitriol" 

Physical Properties. A dense, colorless, oily -looking liquid, 
without odor. 

Chemical Properties. Strong acid ; very avid of water, not only 
dissolving in it, but combining with it, the act evolving consider- 
able heat; chars organic matters by abstracting H and to form 
water (H 2 0) * 

Uses. So important in the arts that the commercial prosperity 
of a country may be measured by the amount of H 2 S0 4 consumed. 



"Experiment. Pour strong sulphuric acid on an equal quantity of sugar 
or strong syrup: the sugar is dehydrated and a mass of carbon left. 



34 INORGANIC CHEMISTRY. 

Properly diluted, it is a refrigerant tonic, but concentrated it is 
a severe caustic. 

Tests. (1) The concentrated acid, if placed on a piece of paper 
or other organic material, will char it. If dilute, it will char the 
paper only after being warmed and concentrated by the evapora- 
tion of its water. (2) Sulphuric acid, or any other sulphate, will 
form with a solution of a barium salt a white precipitate (BaS0 4 ) 
insoluble in nitric or hydrochloric acid. 

IV. Nitrogen Group. 

Nitrogen N 14 

Phosphorus P 31 

Arsenic As 75 

Antimony (Stibium) Sb 12,2 

Bismuth Bi 2 10 

Trivalent and Quinquivalent. This group, as shown 
below, forms a graded series from nitrogen and the negative to 
bismuth at the positive end. 

N P As Sb Bi 

14 31 75 122 2 10 

Sp. gr. 1.83. Sp. gr. 5.67. Sp. gr. G.7. Sp. gr. 9.8. 

Gas, with full A soft solid. Solid. Hard solid. Very hard 

negative ten- solid, 

deneies. Easily volatil- Volatilizable. Difficultly vol- Non-volatiza- 

izable. atilizable. hie. 

Destitute of Some metallic Great metallic Full metallic 

metallic luster, luster. luster. luster. 

Negative ten- Both negative More positive Full positive 

deneies. and positive tendencies. tendencies, 
tendencies. 

The following will exhibit the relations of some of the most 
important compounds : 

Hydrides. Chlorides. Oxides. Sulphides. 

-ous, -ic. -ous, -ic. -ous, -ic. 

NH 3 NC1 3 ........ N3O3, N 2 5 

PH 3 PCI3, PCI5 P 2 3 , P 2 5 P 2 S 3 , P 2 S 5 
AsH 3 AsCl 3 , AsCl 5 As 2 3 , As 2 5 As 2 S 3 , As 2 S 5 
SbH 3 SbCl 3 , SbCl 5 Sb 2 3 , Sb 2 5 Sb 2 S 3 , Sb 2 S 5 
BiCl 3 , Bi 2 3 , Bi 2 5 

Nitrogen occurs uncombined in the atmosphere ; combined in 
some mineral and in all vegetable and animal bodies, especially 
in the more highly organized tissues. 




INORGANIC CHEMISTRY. 35 

Prepared most easily by burning phosphorus in a confined 
space until the oxygen is removed from the air.* Prepared in 
this way it contains small quanti- q 

ties of other gases found in air. To 
prepare it pure, heat ammonium 
nitrite (NH 4 N0 2 -2H 2 0-N 2 ). 

Physical Properties. A color- | fl£ Hh 

less, tasteless, odorless gas, a little Cr^^W M 

lighter than air. g^J V W 

Chemical Properties. Little ten- ^^^ 
dency to combine with other ele- ^^5 
ments, and its compounds, once ^rL 
formed, are very prone to decom- iI^^E^^^^^^^^^^f 
pose, either with violent decompo- ~ r-_^-_-_-_-^r-_ - — - - 
sitionf or gradual putrefaction; Fig. 30. 

neither combustible nor a supporter of combustion ; negatively 
poisonous. 

The Atmosphere. Air, considered by the ancients one of 
the four elements, is neither an element nor a compound. It is 
a mixture J mainly of nitrogen and oxygen, the function of the 
former being to dilute the latter. Miller gives the average com- 
position of air as follows : Volumes 

Nitrogen 77.9") 

Oxygen 20.61 

Carbon dioxide 04 

Aqueous vapor 1.40 

Also traces of nitric acid, ammonia, sodium chloride, ozone, dust. 
bacteria, germs, etc. In the neighborhood of large cities various 

"•Experiment. A flat piece of cork float ing on water supports a capsule 
containing a bit of phosphorus carefully dried. This is ignited and immedi- 
ately covered with a bell jar. The jar is tilled with a dense white cloud from 
the combustion, which ceases only when the oxygen is all consumed. At first 
the air expands and some may be forced out. Upon cooling the water rises to 
take the place of the oxygen, and the white fumes gradually dissolve in the 
water, and the nitrogen is left clear and comparatively pure. 

t Experiment. To tincture of iodine add excess of ammonia-water. Filter 
to separate the precipitated iodide of nitrogen. Put portions of this on separate 
bits of paper and set aside. When dry they explode on the slightest touch. 

X Proofs that air is a mixture: 1) Its constituents are not in atomic propor- 
tions ; (2) air can be made by mechanically mixing the gases ; (3) solvents may 
remove one gas without affecting the others, each dissolving according to its 
own solubility. 



36 



INORGANIC CHEMISTRY. 



other substances are poured into the air from manufactories. 
Yet, owing to the rapid diffusion of gases, the composition of the 
air is almost the same every where. 

Watery Vapor. The higher the temperature the more water 
air will hold. A warm, dry air, when cooled, will appear damp, 
and the temperature at which it begins to deposit its water is 
its dew-point. A cold, damp air, when heated, becomes capable 
of holding more water, and appears dry ; hence the necessity of 
supplying water to the heated air of our rooms in winter, espe- 
cially in cases of bronchitis or catarrhal croup. Even in health 
a very dry air irritates the air-passages, produces dryness of the 
skin and malaise; while a very moist atmosphere retards evapo- 
ration from the skin and lungs, 
raises the body temperature, and 
becomes oppressive. 

Suspended matters in air are of 
a great variety of substances. The 
irritation of dust incident to cer- 
tain trades may cause chronic 
bronchitis, emphysema, and phthi- 
sis. Germs floating in the air are 
believed to be the cause of many 
contagious, infectious, and mala- 
rial diseases. The best disinfect- 
ants* are (a) free ventilation and 
consequent dilution ; (b) chlorine, 
bromine, iodine, and sulphur di- 
oxide. 

Nitrogen Hydride — Ammo- 
nia, NH 3 — Occurs in the effluvia from decomposing nitrogenized 
organic bodies ; for nitrogen and hydrogen unite only in the nas- 
cent state. (See page 20.) First obtained by distilling earners 
dung near the temple of Jupiter Ammon in Libya; hence called 
"ammonia." Obtained by heating clippings of hides, hoofs, and 
horns, f especially of deer, in closed retorts (destructive distilla- 

■■• Disinfectants destroy the power to infect, whether it be due to germs or 
other agent. Germicides destroy germs. Antiseptics prevent putrefaction. Anti- 
zymotics prevent fermentation. Deodorizers destroy offensive odors. 

t Experiment. Mix calcium, potassium, or sodium hydrate with some 
nitrogenous substance, as albumen or clippings of horn, hoofs, flannel, or lean 




Fig. 31. 



INORGANIC CHEMISTRY. 



37 



tion), it was called 'spirit of hartshorn. Coal contains about two 
per cent of nitrogen, which in the manufacture of coal gas comes 
off as ammonia. In washing the coal gas 
the ammonia dissolves in the water. This 
aqua is its commercial source. 

Prepared in laboratory by driving the 
ammonia off from the aqua by means of 

r ^ heat. (Fig. 32.) 

^" Physical Properties 

Transparent, colorless gas, 
of an irritating odor ; very 
.^u.-L^-.J soluble in water, which dis- 
.^KjjiiS solves from 500 to 1,000 
times its own volume.* Ad- 
ministered by in- 
halation as a stim- 
ulant in fainting 
fits, etc., but 
^djjmlk care must be 
taken, for its 
Fig. 33. too liberal Fig. 32. 

use may cause spasm of the glottis or induce a fatal bronchitis. 
Tests. (1) Smell; (2) white fumes with HC1; (3) turns moist- 
ened red litmus paper blue. 
Xiteogex Oxides. 

Monoxide— N 2 0+H 2 0=2HNO=Hyponitrous acid.' 
Dioxide — N 2 2 . No corresponding acid. 
Trioxide— N 2 3 +H 2 0=2HX0 2 =Nitrous acid. 
Tetroxide — N 2 4 No corresponding acid. 
Pentoxide— X0 5 +H 2 0=2HN0 3 =Nitric ac id. 








meat. Heat in a test-tribe. (Fig. 31.) Ammonia gas is evolved, recognized by 
its odor, alkalinity, or by white fumes forming when a glass rod moistened with. 
HC1 is thrust into the tube. 

"Experiment, The absorption of ammonia gas by water may be illus- 
trated by filling a large bottle with the gas by upward displacement (Fig. 32) , 
and closing the mouth with a rubber cork through which passes a glass tube 
sealed at the outer end. If this sealed end be plunged under water and then 
broken off. the water rushes in, forming a fountain. (Fig. 33.) If the water be 
colored with red litmus solution it will become blue as it enters the bottle, 
showing the alkalinity of the solution. 

D 



38 



INORGANIC CHEMISTRY. 




Nitrogen Monoxide — N 2 {Nitrous Oxide — Laughing Gas). 
Prepared by heating ammonium nitrate, as shown in Fig. 34. 
NH 4 N0 3 =N 2 0+2H 2 0. 
Physical Properties. Colorless, odorless gas, of sweetish taste. 

Dentists keep it lique- 
fied under pressure in 
iron cylinders. 

Chemical Properties. 
By the ease with which 
it gives up its O it is a 
supporter of combus- 
tion and life, next to 
O itself. 

Medical. Inhaled, 
diluted with air, it 
produces exhilaration 

Fig. 34. , ., , 

of spirits, muscular 
activity, and then complete anaesthesia. Used in dental and 
other brief minor operations. 

Nitrogen Dioxide — N 2 2 {Nitric Ox- 
ide). Prepared by action of nitric acid 
on copper: 

3Cu+8HN0 3 =:3Cu(N0 3 ) 2 +4fl 2 0+N 2 2 . 
A colorless gas, which, when coming in 
contact with free O, forms red vapors of 
N 2 3 and N 2 4 ; hence a test for free O. 
(Fig. 35.) 

Nitrogen Trioxide — N 2 3 {Nitrous 
Acid — HN0 2 ). Nitrous acid is known 
only in its salts, the nitrites. These are 
produced in nature by the oxidation of 
nitrogenous organic matter in the pres- 
ence of certain forms of microscopic life. 

This nitrification occurs in waters polluted with organic mat- 
ter, and normally in the soil, where the acid so formed combines 
with bases. Hence nitrites in water is evidence of previous con- 
tamination with nitrogenous matter. Further oxidation forms 
nitrates. 

Nitrogen Tetroxide — N 2 4 — occurs in company with N 2 




Fig. 35. 



INORGANIC CHEMISTRY. 



39 



in the brown fumes given off whenever nitric acid is decomposed, 
as in certain laboratory and manufacturing processes. The effect 
of breathing air thus 
contaminated is to pro- 
duce chronic inflam- 
mation of the respira- 
tory tract. If the va- 
por be more concen- 
trated the effects are 
more acute and seri- 
ous. At first there is 
only a cough, in two 
or three hours a diffi- 
culty of breathing, and 
in about twelve hours 
death. The remedy is 
ventilation. 

Nitrogen Pen- 
toxide — N„0- — is of 
no medical interest. 

Nitric Acid— HN0 3 {Aqua Fortis) — occurs in traces in the 
atmosphere and as nitrates in the soil. (See Nitrites.) 

Prepared by distilling a nitrate with sulphuric acid. 

2KN0 3 +H 2 S0 4 =K a S0 4 +2HN0 3 .t 

Physical Properties. Heavy liquid, colorless, but if old and 
exposed to light it may be yellow or orange from presence of 
N 2 3 and N 2 4 . Like all other nitrates, it is soluble in water. 

Chemical Properties. Energetic oxidizer; J corrosive; stains 
skin indelibly yellow. 




Fig. 36.* 



* Experiment. Copper turnings, clippings, or wires are placed in a flask, 
and nitric acid diluted with, half its volume of water is poured in, and the flask 
set in cold water. (Fig. 36.) Red fumes soon fill the flask, but when these have 
escaped the gas appears colorless, turning red, however, on reaching the air. 
The colorless gas is collected over water. 

t Experiment. In the laboratory nitric acid, may be prepared with the 
apparatus shown in Fig. 1-1, page 17. Equal parts of sodium nitrate and sul- 
phuric acid are heated in the retort. The nitric acid produced is vaporized by 
the heat and recondensed in a receiver supported over a beaker and kept cool 
by a wet cloth, over which flows a stream of water from an elevated vessel. 

% Experiment. Into a mixture of strong sulphuric and nitric acids pour 
from a beaker tied to a long stick some warm turpentine. The oxidation is so 
rapid that the turpentine is inflamed. 



40 



INORGANIC CHEMISTRY. 



Medical Uses. The strong acid is an escharotic, coagulating 
the albumen of the tissues; the dilute, a refrigerant tonic. 

Tests. (1) Yellow stain. (2) Add H 2 S0 4 , and then a crystal 
of FeS0 4 dropped in will be colored brown if nitric acid or any 
nitrate be present. • 

PHOSPHORUS (Light-bearer) occurs combined with O in the 
ancient unstratifled rocks. These disintegrate and form soil, from 




Fig. 37. Commercial Preparation of Nitric Acid. 

which the P passes into the organisms of plants, and thence into 
the bodies of animals. First isolated by Brandt (1669) from 
urine ; now obtained from bones. 

Physical Properties. A soft, yellowish solid, resembling un- 
bleached wax. Insoluble in water, but soluble in carbon disul- 
phide, ether, chloroform, oils, etc. 

Chemical Properties. Very inflammable,* so kept under water; 
exposed to' the air, it undergoes a slow combustion, emits the 
odor of ozone, and is luminous in the dark. 

Physiological. Liable to inflame from careless handling, and 
burns by it are difficult to heal. In medicinal doses, a nerve 
tonic and aphrodisiac; in larger quantities a virulent poison and 
gastro-irritant. Sometimes given with homicidal intent, but more 
frequently taken accidentally as rat poison, tips of matches, etc. 
Workmen in match factories suffer from irritation of stomach 

* Experiment, Dissolve some phosphorus in carbon disulphide. Pour 
this on a sheet of filter paper hung on a retort stand. Soon the solvent evapo- 
rates and leaves the phosphorus in such a fine state of division that it inflames 
spontaneously. 



INORGANIC CHEMISTRY. 



41 




Fig. 38. 



and bowels, caries of teeth, necrosis of bones, especially of lower 
jaw, and from fatty degeneration of various organs. This may be 
prevented by 
using a red allo- 
tropic variety, 
which is harm- 
less. 

No good an- C 
tidote. Evacu- 
ate the stom- 
ach ; give cop- 
per sulphate* 
as emetic and 
antidote; old 
turpentine, the 

ozone of which oxidizes the P. Avoid fats, for they dissolve it. 
Tests. (1) Shines in the dark ; (2) emits garlicky odor. 

Phosphorus Hydride — PH 3 (Phospho- 
retted Hydrogen — Phosphine) — occurs mixed 
with other hydrides of P in the gases arising 
from decomposing animal or vegetable mat- 
ters, especially under water ; hence seen as 
the ignis fatuus or "Will o' the wisp" over 
marshes and graveyards. 

Prepared by boiling phosphorus in a so- 
lution of caustic potash.f 

Properties. Colorless gas, of a garlicky 
odor ; inflames spontaneously upon coming 
in contact with the air ; very poisonous. 

Phosphorus Oxides. These are analogous to the oxides of 
nitrogen, and form, on the addition of water, analogous acids. 




Fig. 39. 



"Experiment. Place a clean bit of phosphorus for a minute in a solution 
of copper sulphate. Remove, and note the coating of metallic copper. 

t Experiment. Into a retort, whose delivery-tube dips under water in a 
dish, add liquor potassse and a few bits of phosphorus. Expel the air by pass- 
ing hydrogen or illuminating gas through the retort, or by adding a few drops 
of ether, the vapor of which does the same thing. On applying heat the hydro- 
gen or illuminating gas or ether vapor first escapes, then come bubbles of PH3, 
each of which, as it bursts into the air, ignites spontaneously, forming beautiful 
rings of white smoke rotating on their circular axes. These may ascend to the 
ceiling if the air be still. 



42 INORGANIC CHEMISTRY. 

Phosphorus Pentoxide (P 2 5 ) is produced whenever P burns 
in air* or O; and forms three different phosphoric acids by com- 
bining with one, two, or three molecules of water, thus: 

P 2 5 +3H 2 0=H 6 P 2 8 =2H 3 P0 4 =Orthophosphoric acid. 

P 2 5 +2H 2 0=H 4 P 2 7 =Pyrophosphoric acid. 

P 2 5 -hH 2 0--=H 2 P 2 6 -2HP0 3 =Metaphosphoric acid. 

Orthophosphoric Acid. Never found free, but is widely 
disseminated in the three kingdoms of nature in its salts, the 
phosphates. Being the phosphoric acid most used in medicine 
(the other two are poisonous), it is usually called simply "phos- 
phoric acid." Transparent, odorless, colorless, syrupy liquid. Be- 
ing tribasic, it forms three classes of phosphates by displacement 
of one, two, or three atoms of the basic hydrogen, thus : 

KH 2 P0 4 , K 2 HP0 4 , and K 3 P0 4 . 

In the diluted form (acidum phosphoricum dilutum) it is prescribed 
as a tonic, especially in dyspepsia. 

Tests. Add a few drops of the magnesian fluid (MgS0 4 ,NH 4 CL 
and NH 4 HO, each one part, water eight, parts) ; a white precipi- 
tate indicates phosphoric acid or other phosphate. 

ARSENIC occurs mostly as sulphide, usually associated with 
other metals. The ore is roasted, and the resulting oxide heated 
with carbon (charcoal) gives the metal. This is a brittle, steel- 
gray, crystalline solid, possessing a metallic luster. Heated out 
of contact with air it sublimes; in air it burns with a bluish- 
white flame, emitting the odor of garlic and white clouds of 
As 2 3 . It combines with many elements; the metallic arsenides 
resemble alloys. Used in pyrotechny and in the manufacture 
of shot, pigments, and fly-poison. All its compounds are poi- 
sonous. 

Arsenious Hydride — AsH 3 — Arseniuretted Hydrogen — Arsine 
— is of great practical interest to the toxicologist, as its forma- 
tion constitutes one of the most delicate tests for arsenic. Forms 
whenever hydrogen is generated in presence of an arsenical com- 
pound. 

* Experiment. A little stand in the middle of a dinner-plate supports a 
capsule into which is put a bit of phosphorus freed from adhering water. This 
is ignited and covered with a bell jar. (Fig. 39.) This jar is filled with clouds 
of P2O5, which, aggregating, fall into the plate like a miniature snow-storm. 



INORGANIC CHEMISTRY. 43 

Arsenious Iodide — Asl 3 . Prepared by fusing together atomic 
proportions of its constituent elements. It enters into Donovan's 
Solution, liq. arsenii et hydrargyri iodidi, U. S. P. 

Arsenious Sulphide — As 2 S 3 — occurs native as orpiment. Pre- 
pared by precipitating an arsenious compound with H 2 S. Bright 
yellow powder, insoluble in water or acid solutions, but soluble 
in alkaline. Another sulphide is realgar, AsS 2 . Both are used as 
pigments — the orpiment as a yellow, the realgar as a red. 

Oxides and Acids. 

As 2 3 +3H 2 0=2H 3 As0 3 , (ortho) Arsenious acid. 
As 2 5 -j-3H 2 0= 2H 3 As0 4 , (ortho) Arsenic acid. 

Arsenious Oxide — As 2 3 . Arsenic, White Arsenic, Ratsbane, 
Arsenious Acid. This is not only the most important compound 
of arsenic, but the most important of toxic agents, whether we 
consider the deadliness of its effects or the fatal frequency of its 
administration. When recently made it is in glassy lumps, which 
on exposure become crystalline and opaque. When sublimed it 
is deposited again in brilliant octahedral crystals. It is odorless, 
almost tasteless — slightly sweetish. When powdered arsenic is 
thrown upon water it does not all sink, notwithstanding its heavi- 
ness, but floats, showing a repulsion of the water. Very slightly 
soluble in water, even boiling water dissolving less than two per 
cent. If the water be made acid or alkaline, it dissolves more 
readily. When arsenic dissolves in water it forms arsenious acid, 
H 3 As0 3 . 

There are two officinal solutions, each containing one per cent 
of arsenic: (1) Liq. acidi arseniosi, in which the water is acidulated 
with HC1; (2) Fowler's Solution, liq. potassii arsenitis, in which the 
water is made alkaline by K 2 C0 3 . 

Arsenic Oxide. Arsenic pentoxide is made when arsenious 
oxide (As 2 3 ) is treated with an oxidizing agent, as nitric acid. 
It is quite soluble in water, with which it forms a series of arsenic 
acids (ortho-, pyro-, and meta-) analogous to the phosphoric acids. 

Toxicology of Arsenic. The deadly effect of arsenical compounds 
has been known from remote antiquity, and they have proba- 
bly been more used for homicidal purposes than all other toxic 
agents combined. Although chemistry has made its detection 
easy and certain, arsenic is so cheap, so readily administered to 
the unsuspecting victim, and so deadly, that it is still a favorite 



44 INORGANIC CHEMISTRY. 

with the murderer. Owing to the extensive use of arsenical com- 
pounds as insect-powders (paris green, etc.), and as pigments for 
wall-paper, toys, confectionery, etc., cases of accidental poisoning 
are quite common. 

Few physicians have the training and facilities to undertake 
an extended analysis, but they should all know the simpler tests, 
so as to promptly recognize the nature of the poison and combat 
it more intelligently and successfully. Besides, the physician, 
being early in the case, can by wise precautions prevent breaks 
in the chain of evidence ; protecting the prisoner if innocent, and 
closing loop-holes of escape if guilty. If foul play is suspected, 
he should commit all his observations to writing, for notes to be 
admitted as evidence must be the original ones taken at the 
time. Having collected the urine, faeces, vomit, and the sus- 
pected vehicle of the poison, and having tested some or all of 
them to verify his suspicion, he should place them under seal or 
lock and ; key. He should carefully reserve his opinion, lest he 
do injustice to the innocent or warn the guilty. In case of death, 
the coroner should be notified and an autopsy held, in presence 
of the chemist if possible. The stomach and entire intestinal 
canal, ligated at both ends, half of the liver, the whole brain, 
spleen, one kidney, and any urine remaining in the bladder should 
be saved. These, if possible, should be preserved in separate jars, 
to which a little pure chloroform may be added to prevent de- 
composition. These jars must be new and clean, closed with new 
corks or glass — not zinc caps. They are then to be labeled and 
also sealed and stamped, so they can not be opened without de- 
tection, and as soon as possible turned over to the chemist or 
prosecuting officer. 

The symptoms of arsenical poisoning are those common to all 
intense irritants, viz., nausea, vomiting, burning pain in the epi- 
gastrium, purging, cramps, thirst, fever, rapid pulse, etc., ending 
in collapse. Smallest fatal dose is two grains, and death usually 
occurs in twenty-four hours. 

Treatment. Remove any unabsorbed poison from the, stomach 
by emetics or stomach-pump. The best antidote* is freshly pre- 

*An antidote is something harmless and capable of rendering the poison 
harmless. Since poisons are inert when insoluble, antidotes are usually such 
substances as are capable of combining with the poison to form an insoluble 
and therefore inert compound. 



INORGANIC CHEMISTRY. 



45 



cipitated ferric hydrate, made by adding aqua ammonias to a solu- 
tion of a ferric salt. "Dialysed iron," being a solution of ferric 
hydrate, may be used. It should be given at frequent intervals 
and in tablespoonful doses. 

Tests for Arsenic. In the solid state: 1. Heated on a knife- 
blade over a lamp, it volatilizes with a white smoke, and leaves no 
residue. 

2. Heated in a test-tube it sublimes, and is recondensed in the 
cooler portion of the tube (Fig. 40) as octahedral crystals (Fig. 41). 

3. Heated in a small tube with 
powdered charcoal, the arsenic is re- 
duced as it sublimes, and recondenses 
on the cooler portion of the tube in 
the metallic state. 

In the liquid state: 1. Through the 
solution, acidulated or rendered neu- 
tral, pass H 2 S; a yellow precipitate 
(As 2 S 3 ) falls. 

2. To an aqueous 
solution add a few 
drops of nitrate of 
silver, and then cau- j 
tiously add ammo- 
Fig 41. u ^ d r0 p k v drop, 

till a yellow precipitate, silver arsenite 

(Ag 3 As0 3 ), is obtained, showing the presence of arsenic. 

3. Repeat the preceding, adding copper sulphate instead of 
silver nitrate, and the presence of arsenic is indicated by a green 
precipitate of copper arsenite (Scheele's green or paris green). 

The last two tests may be performed with greater ease* and 
delicacy if the silver nitrate and copper sulphate each be previ- 
ously treated with ammonia until the precipitate first formed is 
barely dissolved, forming solutions of ammonio - nitrate of silver 
and ammonio-sulphate of copper, which are filtered and set aside 
as test reagents. 

The Plating (Reinsch's) Test. Place a thin piece of pure copper 
in the solution acidulated with HC1, and boil. If arsenic be pres- 
ent, it will be deposited as a metallic film on the copper. If the 
solution be then poured off, and the piece of copper, carefully 





Fig. 40. 



46 



INORGANIC CHEMISTRY. 



dried, be heated in a dry test-tube, the film will sublime and con- 
dense on the sides of the tube, and the preceding tests may be 
applied. 

The Hydrogen (Marsh's) Test depends on the fact that AsH 3 is 
always formed whenever hydrogen is generated in the presence 
of any arsenical compound. Generate hydrogen in the usual way 
(Zn+H 2 S0 4 ), and if the chemicals are pure (free from arsenic), 
the gas burns with a pale yellowish flame, without odor, and does 
not stain a porcelain dish held in the flame. Then pour into the 
generator some of the suspected solution. If arsenic be present, 
there is an odor of garlic; the flame becomes bluish- white, and a 
cold porcelain dish held in the jet so chills the flame that only 




Fig. 42. 

the H burns, and the As is deposited on the porcelain as a brill- 
iant metallic film. If the delivery-tube be heated, the passing 
AsH 3 is decomposed, and metallic arsenic deposits in a film of 
the same character as that on the porcelain. 

This may be distinguished from the film formed by antimony 
under similar circumstances by (1) its greater metallic luster, and 
(2) by its dissolving on the addition of chlorinated soda (Labar- 
raque's solution); (3) moisten the spot with nitric acid; evapo- 
rate the acid; a white stain is left, which is colored a red by 
AgN0 3 and yellow by H 2 S. The flame should now be extin- 
guished and the delivery-tube made to dip into a solution of 
AgN0 3 . This will be blackened, and, if overlaid with aqua am- 



INORGANIC CHEMISTRY. 47 

monise, a yellow precipitate will appear at the junction of the 
two fluids. 

ANTIMONY (stibium) occurs native, but usually as a sul- 
phide. Prepared by roasting the sulphide, and heating the oxide 
thus obtained with charcoal. 

Properties. A bluish-white, brittle, crystalline solid, with a 
brilliant metallic luster. Resembles metals and forms alloys. 
In chemical properties it plays the role of positive and negative 
radical with equal facility. 

Used in alloys, as type metal, Babbitt's metal, britannia, etc., 
to which it gives hardness and causes them to expand and fill the 
molds on solidifying. The metal is not used in medicine, most 
of the compounds being obtained from the sulphide. 

Antimonious Hydride — SbH 3 (Antimoniuretted Hydrogen — 
Stibine), corresponding to AsH 3 . This gas is formed wherever 
hydrogen is generated (nascent) in presence of a reducible anti- 
mony compound. 

Antimonious Chloride — SbCl 3 . At ordinary temperatures 
a yellow semi-solid ; hence called butler of antimony. On addition 
of considerable water it decomposes, precipitating a white powder, 
the oxychloride (SbO . CI),* formerly called powder of algaroth. 

Oxides and Acids of Antimony. 

Sb 2 3 +H 2 0— 2HSb0 2 — (meta) Antimonious acid. 
Sb 2 5 +H 2 0=2HSb0 3 — (meta) Antimonic acid. 

Antimonious Oxide— Sb 2 3 . Prepared by treating the oxy- 
chloride with sodium carbonate to remove the chlorine. A whit- 
ish, insoluble, volatilizable powder. 

Antimony and Potassium Tartrate— (SbO )KTf {Tartar 
Emetic). Prepared by treating Sb 2 3 with the bi tartrate of potas- 
sium, thus : 

2KHT+Sb 2 3 =: 2(SbO)KT+H 2 0. 

Sweetish, metallic taste ; soluble in water and slightly so in alco- 
hol. Dissolved in Sherry wine it forms vinum antimonii, U. S. P* 
It enters also into unguentum antimonii and syrupus scilloz compos- 
ite, U. S. P. 

*SbO and BiO, called respectively antimonyl and bismuthyl, are univalent 
radicals, because two valences of the trivalent element being satisfied by the 
bivalent O, only one free valence is left. 

t(T) is used to represent the tartaric acidulous radical (C4H4O6). 



48 INORGANIC CHEMISTRY. 

Antimonious Sulphide — Sb 2 S 3 , the principal ore of anti- 
mony ; occurs native in black, lustrous masses. It may be precip- 
itated from any antimonial solution by H 2 S as an orange powder, 
which is black when thoroughly dried. 

Poisoning by antimony occurs oftenest with tartar emetic, for 
that salt is used more than all the other compounds of antimony. 
The symptoms are those referable to gastro - enteric irritation. 
Fortunately the salts of antimony are emetic, and cause sponta- 
neous evacuation of the stomach. Encourage this, and give tannic 
acid or ferric hydrate, which will form an insoluble compound. 

The presence of antimony may be detected by (1) orange pre- 
cipitate with H 2 S; (2) by Marsh's test (see page 46). 

BISMUTH occurs native and as sulphide. Prepared by roast- 
ing the sulphide in air, and reducing the resulting oxide with 
charcoal. 

Properties. A brittle, white metal, with a bronze tint ; volatil- 
izes at a white heat. Forms compounds closely analogous to those 
of Sb, but is more positive, and plays the negative role with less 
facility. 

Used in alloys ; e. g. pewter and stereotyping metal ; the latter 
melts in boiling water. 

Bismuth Nitrate — Bi3N0 3 . Formed by treating bismuth 
with nitric acid. Dissolves in a little water, but if much water 
be added it decomposes, with precipitation of 

Bismuth Subnitrate — BiON0 3 (Bismuth Oxynitrate) — a 
white, tasteless powder, much used in medicine and as a cosmetic 
(pearl white). 

Bismuth Subcarbonate — (BiO) 2 C0 3 . Similar to the pre- 
ceding in constitution, properties, and uses. 

Bismuth and Ammonium Citrate. Obtained in pearly scales 
by dissolving the citrate in dilute ammonia-water, evaporating to 
a syrupy consistence and spreading on glass to dry. Being very 
soluble it is the preparation used in making the popular elixirs 
of bismuth. 

Physiological. The bismuth salts are tonic, sedative, mildly 
astringent and antifermentative. Used to allay gastro-intestinal 
irritation. Occasionally the irritation is increased from presence 
of arsenic which unscrupulous manufacturers often fail to remove 
as the Pharmacopoeia directs. When preparations of bismuth are 



INORGANIC CHEMISTRY. 49 

taken, the stools are blackened by the sulphide formed with the 
H 2 S in the intestines. In severe cases of diarrhoe, with acid fer- 
mentation, this blackening does not occur, and its reappearance 
is a sign of improvement. 

Tests. (1) H 2 S or NH 4 HS gives brownish-black precipitate; 
(2) the concentrated solution poured into water forms a white 
precipitate. 

V. Boron Group. 

Boron B 11 

Occurs as a constituent of boracic acid and borax (sodium 
borate). Has two allotropic forms, amorphous and crystalline, 
corresponding to coal and diamond. Forms only one oxide 
(B 2 3 ), which, combining with water, forms an acid: 
B 2 3 +3H 2 0=H 6 B 2 6 =2H 3 B0 3 — Boric acid. 

Boric or Boracic Acid occurs as pearly scales, soluble in 
water; feeble acid; an unirritating antiseptic. Boiled with 
glycerine it forms boroglyceride, a soluble, neutral, tasteless 
liquid used to preserve foods. 

Test. Compounds of boron, especially when moistened with 
sulphuric acid, color the flame green. 

VI. Carbon Group. 

Carbon (carbo, a coal) C 12 

Silicon (silex, a flint) Si 28 

Each element is quadrivalent, and occurs in three allatropic 
forms. The saturated oxide of each forms with water a dibasic 
acid: CO.-f-H.O-H.CC^, Carbonic acid. 

Si0 2 +H 2 0=H 2 Si0 3 , Silicic acid. 

CARBON occurs free in its three allotropic forms, diamond, 
graphite, and coal; combined in carbonates and in all animal 
and vegetable substances. All its forms are probably traceable 
to organized life. 

Diamond. Geological history unknown; transparent crystal- 
line body of great brilliancy; hardest substance known. Used 
as a gem and for cutting glass, etc. 

Graphite (to write). Owing to its resemblance to lead it has 
been called black lead or plumbago; almost pure carbon. Used for 
pencils, crucibles, stove polish, etc. 



50 



INORGANIC CHEMISTRY. 



Coal. Mineral coal is a black substance, compact in texture, 
the remains of vegetable life of past ages. Charcoal is obtained 





Fig. 44. 

by burning heaps of wood (Fig. 43) with a limited supply of air. 

The volatile constituents pass off, leaving the carbon as a light, 
porous substance, retaining the'form and 
structure of the wood. Animal charcoal 
is made by heating animal matters in 
closed iron retorts. Charcoal, especially 
animal, is a valuable absorbent of odor- 
ous gases * and coloring matters.f 

Properties. Free carbon is solid at all 
temperatures, and insoluble in all men- 
strua. Ordinarily, free carbon is unaf- 
fected by chemical agents, but at high 
temperatures it surpasses all other ele- 
ments in its avidity for 0. Hence it is 
used to separate the metals from their 




Fig. 45. 



oxides.J 



* Experiment. Fill a test-tube with ammonia gas over mercury. (Fig. 44.) 
Introduce a piece of charcoal recently heated. The gas is absorbed as is shown 
by the rapid rise of the mercury. 

t Experiment. To a solution of indigo, cochineal, or potassium perman- 
ganate or beer in a flask, add some animal charcoal, shake up and filter. The 
filtrate is colorless, and in case beer is used it has also lost its bitter taste. 
(Fig. 45.) 

X Experiment. Into a slight depression in a piece of charcoal lay some 
metallic oxide— e. g. lead oxide— heat with a blow-pipe. The oxide is reduced 
by the heated charcoal around it, and globules of the metal appear which 
coalesce into a bright button. 



INORGANIC CHEMISTRY. 



51 




Carbon Monoxide — CO — occurs whenever carbon is burned 
with an insufficient supply of air, as in anthracite stoves and 
furnaces, and in coal gas, but never occurs in nature. 

Prepared in the laboratory by heating oxalic acid, or potas- 
sium ferrocyanide, with sulphuric acid. 
Properties. Colorless, odorless, taste- 
less gas ; burns with a pale blue flame ; 
very poisonous, combining with the col- 
oring matter of the blood corpuscles, 
and destroying their oxygen - carrying 
power. Artificial respiration is of little 
use. Transfusion of blood is the most 
promising treatment. After death the 
blood remains scarlet. The sources of 
danger are open charcoal fires, defective 
draught in stoves and chimneys, and illuminating gas escaping 
into bed-rooms. 

Carbon Dioxide — C0 2 . 

C0 2 +H 2 04-H 2 C0 3 — Carbonic acid. 
Occurs sparingly (.0004) in the atmosphere, as a result of ani- 
mal respiration, vegetable decay, 
and combustion. Plants absorb 
it, appropriating the carbon and 
returning the oxygen to the air."* 
It often accumulates in cellars, 
beer-vats, wells, etc., where it is 
called choke-damp. 

Prepared by burning carbon, 
but most conveniently in the lab- 
oratory by decomposing a carbon- 
ate with an acid. 
CaC0 3 +2HCl=CaCl 2 +H 2 0+C0 2 . 





Fig. 47. 
Physical Properties, 



Fig. 48. 

Transparent, colorless gas, of a pungent 



* Experiment. Stick several fresh sprigs of mint into a funnel sealed up 
at the little end. Fill with carbonated water, invert in a glass of the same (Fig. 
46), and place in sunlight. Soon minute bubbles will appear on the under sur- 
faces of the leaves and, coalescing into larger bubbles, will rise and collect in 
the neck of the funnel. When in sufficient quantity, a lighted taper will show 
it to be oxygen. 



L.. 



52 



INORGANIC CHEMISTRY. 




odor and sour taste. One and a half times as heavy as air.* 
Water dissolves its own volume. Soda-water is only a solution 

of this gas under pressure.f 
Chemical Properties. Nei- 
ther^burns nor supports com- 
bustion. \ In water it exists 
as carbonic acid — H 2 C0 3 * 
On attempting to concen- 
trate this dilute solution the 
acid decomposes again into 
water and C0 2 ; hence wet 
litmus reddened by it be- 
Fi £- 49 - comes blue again on drying. 

Tests. (1) The gas (15 per cent and over) extinguishes a flame 
(Fig. 49) ; (2) precipitates lime-water (Fig. 51) ; (3) car- 
bonates effervesce on adding a strong acid. (Fig. 50.) 

Physiological. If the gas be undiluted death is im- 
mediate from spasm of the glottis. If somewhat dilute 
(15 to 30 per cent) there is loss of muscular power, an- 
aesthesia, and death without a struggle. If quite dilute 
(5 to 10 per cent) headache, giddiness, muscular weak- 
ness, and sometimes vomiting and convulsions occur. 

The effects are more serious if the C0 2 comes from combustion 
or respiration, because of the removal of oxygen and the admixt- 
ure of the deadly CO and animal exhalations. 

Treatment. Fresh air, artificial respiration, and stimulation. 
The preventive is ventilation. 

Ventilation. More than 7 parts of C0 2 in 10,000 of air is 




Fig. 50. 



* Experiments. To show the weight of carbon dioxide : (1) Pour it from 
one vessel to another. (2) Blow soap bubbles and allow them to fall into a wide 
vessel containing this gas. As soon as they reach the surface of the gas they 
stop and float upon it. (3) Pour a large beakerful of the gas into a light paste- 
board box that has been balanced on a pair of scales. The box will at once 
descend. This gas accumulating in wells may be bailed in buckets, and tested 
by being poured upon a lighted candle. This is illustrated in Figs. 47 and 48. 

t That water will dissolve a greater quantity of carbon dioxide under press- 
ure is shown by the rapid evolution of the gas whenever a bottle of soda or 
other carbonated water is opened and the pressure thereby removed. 

X Set a candlestick, holding several lighted tapers at different heights, in a 
large jar. (Fig. 49.) Carbon dioxide is introduced at the bottom, and extin- 
guishes the tapers one by one as the vessel fills up to their levels. 



INORGANIC CHEMISTRY. 



53 



oppressive. Taking this as the maximum impurity allowable, 
3,000 cubic feet of fresh air per hour is needed by each person, 
and more in case of disease or when lamps are burning. To 
secure this in a room containing 1,000 cubic feet (10x10x10) the 
air must be changed three times an hour. This would give a 
draught not uncomfortable or injurious. If the draught be prop- 
erly distributed, a breathing space of 500 cubic feet changing 





Fig. 51.* Fig. 52. 

six times an hour would be unobjectionable. Ventilation may 
be secured in two ways, by diffusion and by draught. 

Diffusion. Gases mingle more rapidly, liquids more slowly, 
to make a mixture of uniform density. 

When two gases of different* densities are separated by a 
porous partition, they mingle, the lighter passing through more 
rapidly than the heavier, the rapidity being in inverse ratio to 
the square roots of their densities.f 

* Experiment. Two Wolff bottles are half rilled with lime-water and 
arranged as in Fig. 51. Placing the rubber tube in his mouth, the operator can 
inspire through one bottle and expire through the other. The small amount of 
carbon dioxide in the inspired and the larger amount in the expired air is 
shown by a white precipitate, slight in the one and dense in the other bottle. 

f Experiment. Cement a porous earthenware battery cup at its open end 
to the top of a funnel tube, the end of which dips into a beaker of colored 
water. Support on a stand, as in Fig. 52. Bring down over the cup an inverted 
bell jar of hydrogen. The light H diffuses so much faster into the cup than 

E 



54 



INORGANIC CHEMISTRY. 





Fig. 54. 



Fig. 53. 



This diffusion is more active in winter than in summer, be- 
cause of the greater difference in density of the warm air within 
the house and the cold air 
without. Damp walls are 
unhealthful mainly because 
being no longer porous they 
prevent this diffusion. 

N Draught is caused by the 

warm air expanding and ris- 
ing and cold air rushing in to 
take its place. The gaseous 
products of combustion and 
respiration reach the ceiling 
before there is time for perfect diffusion, and 
accumulate there, making this the foulest part of the room. 
(Fig. 53.) This accumulation extends down to the level of the 

draught exit. (Fig. 54.) 
Hence the exit should be 
near the top of the room. 

Cyanogen — CN or Cy. 
Univalent because N m can 
satisfy only three valences 
of C IV . A compound nega- 
tive radical resembling in 
its chemical behavior the 
elements of the chlorine 
group. 

Prepared by strongly 
heating mercuric cyanide.* 
Hg(CN) 2 =Hg+2CN. 
A colorless gas, smell- 
ing like peach kernels. 
Burns with a peach-blossom flame; unites with metals to form 
cyanides, the most important being, 

the air diffuses out of it, that hubbies of gas escape rapidly through the water. 
Remove the hell jar and the conditions are reversed. The H now diffuses so 
rapidly out of the cup that the water is sucked up the tube. 

* If mercuric cyanide can not be obtained, a mixture of two parts of thor- 
oughly dried potassium ferrocyanide and three parts mercuric chloride may 
be- used. (Fig. 55.) 




Fig. 55. Preparation of Cyanogen." 



INORGANIC CHEMISTRY. 55 

Hydrocyanic Acid — H(CN), or HCy — (Prussic Acid, Hydro- 
gen Cyanide). Occurs in bitter almonds, cherry-laurel water, etc. 

Properties. Colorless liquid, having an odor like peach ker- 
nels. For medical purposes only a dilute (2 per cent) solution is 
used, and the dose is from two to five drops. 

Toxicology. All the cyanides are very poisonous. One drop 
of the pure acid produces immediate death, and three grains of 
potassium cyanide kills in a few minutes. The respiratory centers 
are paralyzed, and the victim falls.and dies in convulsions. Poison- 
ing is liable to occur from handling the acid or the cyanides which 
are largely used in the arts, or from eating vegetable products, e. g. 
peach and cherry seeds containing amygdalin, a substance easily 
decomposing into prussic acid and other products. Owing to the 
rapid action of the poison, antidotes are usually impracticable. 
Use artificial respiration and stimulate. If the patient survive 
an hour, the prognosis is good. 

Tests. (1) Its odor; (2) silver nitrate — white precipitate solu- 
ble in boiling HN0 3 ; (3) add ammonium sulphydrate, evaporate 
to dryness, and then add ferric chloride — a blood red color. 

Cyanates. Cyanic acid (HCyO) and ammonium cyanate 
(NH 4 CyO) are the most interesting. The latter on being heated 
forms urea. 

Sulphocyanates are sulpho-salts corresponding to to the cy- 
anates (oxy-salts), and are good illustrations of the facility with 
which S forms series of compounds analogous to those of O. They, 
especially the potassium and sodium salts, are used as test reagents. 

Compound Cyanides. Cyanogen shows a great tendency 
to form complex radicals, especially with iron ; as, ferrocyanogen 
[Fe^CX)/] IV or (FeCy 6 ) IV , and ferricyanogen [Fe/^CN)^ 1 ]^ or 
(Fe 2 Cy I2 ) VI . These two radicals contain ferrous and ferric iron 
respectively, and with hydrogen form acids known as hydro- 
ferrocyanic acid, H 4 FeCy 6 (tetrabasic), and hydroferricyanic acid, 
H 6 Fe 2 CN I2 or H 6 Fe 2 Cy I2 (hexabasic) ; the salts of these acids 
are termed ferrocyanides and ferricyanides. 

Potassium Ferrocyanide — K 4 FeCy 6 — commonly called yel- 
low prussiate of potash, and potassium f err icy anide — K 6 FeCy I2 — red 
prussiate of potash, are important test reagents. 

The carbon compounds will be further considered under the 
head of Organic Chemistry. 



56 INORGANIC CHEMISTRY. 

SILICON (also called silicium) resembles carbon, and occurs 
in three allotropic forms corresponding to coal, graphite, and 
diamond ; most abundant element after oxygen. It exists in only 
a few compounds, but they constitute the larger part of the earth's 
crust. Its principal compound is — 

Silicic Oxide — S10 2 — occurring as flint, sand, rock-crystal, 
etc. ; with water it forms silicic acid. Clay, soapstone, asbestos, 
etc. are native silicates. Melted with the carbonates of the al- 
kalies and alkaline earths it forms glass. If the alkali be in 
excess the product is soluble glass, which is much used in making 
surgical dressings. 

THE METALS. 

Occurrence. Some, as gold and copper, occur free, but most of 
them are found combined with non-metallic elements, especially 
sulphur and oxygen. 

Preparation. If combined with sulphur the ore is roasted 
until the sulphur is burned out, leaving the metal as an oxide, 
which is then heated with carbon to remove the oxygen, thus: 
ZnS+0 3 =ZnO+S0 2 ; then, ZnO+C=CO+Zn. 

Physical Properties. Very opaque, with a "metallic luster" 
(in fine powder, a dull black) ; bluish gray, varying between the 
pure white of silver and the dull blue of lead. Yellow gold and 
red copper are exceptions. In weight, varying between lithium, 
specific gravity 0.58, and platinum, specific gravity 21.50. Most 
are solid, except mercury (liquid) and hydrogen (gaseous). All 
are absolutely insoluble. 

Chemical Properties. Electro-positive, possessing great affinity 
for the non-metals and other electro - negative radicals. When 
two metals are fused together the product is an alloy. If one of 
the metals be mercury, it is called an amalgam. Alloys are not 
chemical compounds, but mixtures, for the metals do not unite 
in definite proportions, and the alloy is not a new substance, but 
one with properties intermediate between those of its constituent 
metals. 

Used mostly in the arts. Of the fifty-five metals only about 
twenty -six, or rather compounds of these, enter the materia 
meflica, and merit our notice. 



INORGANIC CHEMISTRY. 



57 



I. Metals of the Alkalies. 

Cjesium Cs 133. 

Eubidium Rb 85.4 

Potassium (Kalium) K 39.1 

Sodium (Natrium) Na 23 

Ammonium (NH 4 ) 18 

Lithium Li 7 

Univalent; very electro-positive, so that when combined, un- 
less it be with a strongly electro-negative (acidulous) radical, they 
form very alkaline compounds (hence the name). The positive 
affinities, as in the other groups, increase with the atomic weights. 
All their compounds are soluble. 

Cjesium and Eubidium. Bare metals, occurring in small 
quantities with potassium. Discovered in 1860 by means of the 
spectroscope, and named from the colors of their lines in the 
spectrum (ccesius, sky blue, and rubidus, dark red). Of no medical 
interest as yet. 

POTASSIUM occurs only in compounds. Prepared by heating 
one of its oxygen compounds with charcoal in an iron retort 





Fig. 56. Fig. 57. 

(Fig. 56) (K 2 C0 3 +2C=3CO+K 2 ). The metallic K distills over 
and condenses in the flat receiver shown in the figure. 

Physical Properties. Soft as wax; lighter than water; silvery 
luster when freshly cut, but quickly tarnishes. 

Chemical Properties. Intensely electro-positive ; hence it pos- 
sesses great affinity for the non-metals;* takes O from H 2 0, even 

* Experiment. Potassium inflames spontaneously when lowered into a jar 
of chlorine. Warmed with iodine or dropped into bromine it explodes violently. 
This should be done under a tubulated bell jar, because the potassium is scat- 
tered in every direction 



58 INORGANIC CHEMISTRY. 

as ice,"* setting fire to the escaping H, giving the flame the violet 
color characteristic of K. (Fig. 57.) 

Potassium Carbonate — K 2 C0 3 . Obtained as an impure solu- 
tion ("lye") by lixiviating the ashes of plants, especially forest 
trees. This, evaporated to dryness, forms "concentrated lye." 
This in turn, when purified, forms "pearl-ash," which is further 
purified for medicinal use. Sometimes made by burning cream 
of tartar and lixiviating the residue, hence called salts of tartar. 
A white semi-crystalline or granular powder. C0 3 being a weakly 
acidulous radical K 2 C0 3 is very alkaline, even caustic. 

Acid Salts. Salts are formed by a metallic radical displacing 
the basic H of an acid. If all the H be displaced, the result is a 
normal salt, as, H 2 S0 4 -f-K 2 =K 2 S0 4 +H 2 . But if part of the basic 
H of the acid remains, it is called an acid salt, as, H 2 S0 4 +K = 
KHS0 4 +H. Sometimes acid salts are called "bi" salts, because 
the proportion of the acidulous radical to the basylous is twice 
as great as in the normal ; e. g. KHS0 4 is called potassium bisul- 
phate, because the proportion of the acidulous radical S0 4 to the 
basylous radical K is twice as great as in the normal sulphate, 
K 2 S0 4 . 

Potassium Bicarbonate — KHC0 3 . Although an acid salt 
in constitution, it is alkaline in reaction, on account of the weak- 
ness of its acidulous radical. Made by passing C0 2 into a solution 
of K 2 C0 3 . The reaction is as follows : 

K 2 C0 3 +H 2 OH-C0 2 =2KHC0 3 . 

Potassium Bitartrate — KH (C 4 H 4 6 ) or KHT — Cream of 
Tartar. Prepared similarly to the above, by adding tartaric acid 
to a solution of the normal tartrate, thus : K 2 T+H 2 T=2KHT. It 
exists naturally in grape juice, and, being insoluble in an alco- 
holic menstruum, is precipitated on the sides of the wine casks 
whenever vinous fermentation sets in. This is its commercial 
source. 

Other Salts. Most salts of K are made by treating the car- 
bonate with the appropriate acid, e. g. : 

The- chloride— K 2 C0 3 +2HC1=2KC1+H 3 0+C0 2 . 

The sulphate— K 2 C0 3 +H 2 S0 4 =K 2 S0 4 +H 2 0+C0 2 , etc. 

* Experiment. Load a strong toy cannon with gunpowder. On the fuse 
lay a small bit of potassium. Touching it with a piece of ice fires the cannon. 



INORGANIC CHEMISTRY. 59 

The decomposition is attended with an effervescence of C0 2 . 
It is the formation of this volatile compound that determines the 
reaction. (See Volatility, page 19.) 

But the following salts are not made in this way: 

Potassium Hydrate — KHO — Caustic Potash — maybe made 
experimentally by the reaction of metallic K on water, thus : 

H 2 0+K=KH0+H. 

But made in the shops by boiling K 2 C0 3 with slaked lime, thus : 

K 2 C0 3 +Ca2HO=CaC0 3 +2KHO. 

The insoluble CaC0 3 (chalk) sinks to the bottom, and the 
KHO dissolves in the supernatant liquid, which when clear is 
poured off (decanted). This watery solution, if of proper strength 
(§j-Oj), forms li Liquor potassce, U. S. P." If this solution be evap- 
orated to a syrupy consistence and poured into molds, it forms 
the stick caustic potash. KHO is very alkaline, and a powerful 
cautery. 

Exposed to the air it absorbs C0 2 and forms carbonate: 
2KH0+C0 2 =K 2 C0 3 +H 2 0. 

Potassium Iodide — KI: 

6KHO+6I=5KI+KI0 3 +3H 2 0. 

The color disappears because the I goes to form colorless salts. 
Prepared thus, the KI is contaminated with KI0 3 (K-Iodate).* 
But if the mixture be strongly heated the 3 is driven off and the 
KI alone remains. The addition of charcoal facilitates the removal 
of the 3 . 

Potassium Bromide — KBr — maybe made similarly to the 
above. 

Sodio-Potassium Tartrate — NaKT. Rochelle Salt. A neu- 
tral salt made by boiling acid potassium tartrate with sodium bi- 
carbonate. KHT+NaHC0 3 =NaKT+H 2 0+C0 2 . 
This is the reaction that occurs in baking with cream of tartar 
baking powders. 

Potassium Hypochlorite — KCIO. Made by passing chlorine 
into a cold solution of KHO. Yields free chlorine. The ordi- 

* Experiment. The presence of KIO3 in a commercial specimen of KI may- 
be recognized by boiling a little starch in a test- tube, dissolving a crystal of the 
suspected salt, and then adding a few drops of a strong solution of tartaric acid; 
if KIO3 De present, I will be liberated, and a blue color struck with the starch. 



60 INORGANIC CHEMISTRY. 

nary bleaching solutions (Labarraque's Solution or Javelle water) 
are solutions of impure sodium or potassium hypochlorite. 

Tests for Potassium. (1) If the suspected solution be concen- 
trated, add H 2 T and get a precipitate of KHT.* (2) Platinic chlo- 
ride (PtCl 4 ) gives a yellowish precipitate. But the PtCl 4 is very 
costly, and all the potassium compounds so soluble that the above 
tests are but little used. The most convenient is the (3) flame 
test: dip the end of a clean platinum wire in the suspected solu- 
tion, and hold in the colorless Bunsen or alcohol flame and notice 
the yiolet color. 

SODIUM occurs very abundantly as sodium chloride, or com- 
mon salt, from which almost all the sodium compounds are now 
obtained instead of from ashes of seaweeds, as formerly. The 
preparation and properties of sodium and its compounds are so simi- 
lar to those of potassium that we will omit their separate con- 
sideration. So much alike are the salts of the two metals that 
the choice between them is usually governed by considerations 
of economy, convenience, solubility, fashion, etc. On exposure to 
the atmosphere the sodium salts usually have a tendency to efflor- 
esce, while the potassium salts tend to deliquesce. 

Tests. No good precipitant ; for all the compounds of sodium 
are soluble. However, the strong yellow color it gives a flame is 
a very delicate test ; in fact, too delicate, for it shows traces of 
sodium in almost every thing. 

AMMONIUM. When ammonia gas (NH 3 ) combines with an 
acid, it appropriates the basic hydrogen and forms a salt in which 
NH 4 is the positive radical ; e. g. : 

NH 3 +HC1=NH 4 C1, corresponding to KC1 or NaCl; 

NH 3 +HHO=NH 4 HO, corresponding to KHO or NaHO; 

NH 3 +HN0 3 =NH 4 N0 3 , corresponding to KN0 3 or NaN0 3 ; 

2NH 3 +H 2 S0 4 =(NH 4 ) 3 S0 4 , corresponding to K 2 S0 4 or Na 2 S0 4 . 
This radical plays the role of a metal, like K and Na, and is 
called Ammonium. Does not exist uncombined, although Weyl 
claims to isolate it as a dark-blue liquid metal.f We can obtain 

*The addition of alcohol makes the test much more delicate. 

t Experiment. The supposed free ammonium. Sodio- ammonium is pre- 
pared by heating sodium in a sealed tube with ammonia gas. This is in turn 
heated with ammonium chloride in a sealed tube. A dark blue liquid, with me- 
tallic luster, is obtained, but soon decomposes into ammonia gas and hydrogen. 



INORGANIC CHEMISTRY. 61 

it as an amalgam by the reaction between sodium amalgam and 
ammonium chloride.* 

Ammonium Hydrate — NHVEO — Caustic Ammonia — is formed 
in solution whenever ammonia gas (NH) dissolves in water, thus: 
NH 3 +H 2 0=NH 4 HO. It has been already stated that the watery 
solution of a fixed substance is called a liquor; of a volatile sub- 
stance, an aqua. In like manner alcoholic solutions of fixed sub- 
stances are called tinctures, and of volatile, spirits. There are four 
U. S. P. solutions of ammonia: 

Aqua ammonice 10 per cent 

Aqua ammonice fort i or 26 " 

Spiritus ammonice 10 " 

Spiritus ammonice aromaticus. 

In all these solutions NH 4 HO exists, but has never been iso- 
lated, because whenever we attempt to evaporate the water or 
alcohol the NH 4 HO decomposes into NH 3 + H 2 0. Ammonium 
hydrate is very alkaline. 

Ammonium Hybrosulphide — NH 4 HS — occurs in decompos- 
ing nitrogenous, sulphurized organic bodies. Made by saturating 
a solution of NH 4 HO with H 2 S. A yellowish solution ; used as 
a test reagent. 

Ammonium Carbonate— (NH 4 ) 2 C0 3 . Ammonii Carbonas, U. 
S. P. — Sal volatile — is prepared by heating a mixture of NH 4 C1 
and chalk (CaC0 3 ) up to the temperature at which (NH 4 ) 2 C0 3 
would be volatilized, when the following reaction will occur: 

2NH 4 Cl+CaC0 3 -CaCl 2 +(]S x H 4 ) 2 C0 3 . 
(See Volatility, page 19.) Very prone to absorb C0 2 from the 
atmosphere and become bicarbonate unless NH 4 HO be added. 

Other salts may be made by adding the appropriate acid to 
the carbonate or hydrate of ammonium. If we use the carbonate, 
we can tell when acid enough has been added by the cessation of 
effervescence. If the hydrate be used there is no effervescence, 
and our only guide is the point at which the solution becomes 

* Experiment. To some mercury in a test-tube add sodium, small bits at 
a time. On this sodium amalgam pour a strong solution of ammonium chlo- 
ride. Sodium chloride and ammonium amalgam are formed. 

(Xa+Hg)+NH 4 Cl=NaCl+(NH 4 +Hg). 
The ammonium amalgam swells up and soon decomposes — (NH4 + Hg)=NH3-f 
H+Hg— the gaseous NH3 and hydrogen escape, and only the mercury remains. 



62 INORGANIC CHEMISTRY. 

neutral in reaction. This is determined by the use of test papers. 
These are made of white, unsized paper, steeped in a blue vege- 
table pigment called litmus, which is reddened by acids and restored 
to its blue by alkalies. 

Physiological. The hydrate and carbonate are alkaline irri- 
tants, like the corresponding K and Na compounds, though in 
less degree. They, moreover, give off NH 3 , which, though irri- 
tating to the respiratory tract, is a valuable stimulant in fainting 
fits, etc. Two drams of aqua ammonise have killed. The treat- 
ment, as for all alkalies, is to give a dilute acid or some oil. 

Tests. (1) An ammonium salt warmed with liq. potassse gives 
off NH 3 , recognized (a) by its odor, (6) its forming a white cloud 
of NH 4 C1 when a glass rod dipped in the HC1 is held over the 
vessel, and (c) its changing moist red litmus to blue. (2) Heat 
the dry ammonium salt and it volatilizes. 

LITHIUM. Sparingly but widely distributed in nature, espe- 
cially in the waters of certain springs. Lightest of the solid ele- 
ments. Its salts closely resemble those of sodium. 

Physiological. Lithium urate being by far the most soluble 
compound of uric acid, salts of lithium, especially the carbonate, 
are given to gouty persons to promote the elimination of uric 
acid, which accumulates in that disease. 

Test. It colors the flame a beautiful carmine red. 

Analytical. To determine whether a salt be a compound of 
K, Na, NH 4 , or Li, heat samples of each; the one that volatilizes 
is the salt of NH 4 . Confirm this by boiling with KHO and get- 
ting the odor of ammonia. To the other three salts apply the 
flame tests, getting the violet for K, yellow for Na, and carmine 
for Li.* 

II. Metals of the Alkaline Earths. 

Barium Ba ..137 

Strontium Sr... 87.6 

Calcium Ca. 40 

Magnesium Mg 24 

-The delicate violet of K may be masked by the intense yellow of Na, but 
•can be seen if observed through a piece of blue glass, a medium that absorbs 
the yellow light. 



INORGANIC CHEMISTRY. 63 

Bivalent ; their oxides and hydrates are very alkaline, but of 
an earthy character. Their positiveness or basicity, as in other 
groups, is in the order of the atomic weights. Their carbonates 
are decomposable by heat and insoluble in water, unless it con- 
tains H 2 C0 3 in solution. Their sulphates increase in solubility 
from the insoluble barium salt to the very soluble magnesium 
sulphate. 

BARIUM. — Of little interest to the medical student, except 
that its compounds are poisonous. Barium sulphate is very in- 
soluble ; hence (1) the antidote of barium is some soluble sul- 
phate, and (2) barium solutions (nitrate and chloride) are delicate 
tests for sulphates, and vice versa. (See Insolubility, page 19.) 
Barium gives the name a green color; hence used (nitrate) in 
pyrotechny to make the green or Bengal light. * 

STROXTIUM. Of little importance, except that its nitrate 
is used in pyrotechny to make the red light. j 

CALCIUM. Never free, but its compounds are very abun- 
dant, as limestone, gypsum, etc. Calcium salts are necessary to 
animal life, the teeth and bones consisting mainly of calcium 
phosphate. 

Calcium Chloride — CaCl 2 . 

Made: CaC0 3 -j-2HCl=CaCl 2 -f-H 2 0+C0 2 . 

A white salt ; very avid of water and deliquescent ; used to 
dry gases. 

Calcium Carbonate — CaC0 3 . Abundant as limestone, mar- 
ble, corals, chalk, and shells of the Crustacea, mollusks, etc. Chalk 
consists of microscopic shells. Precipitated chalk is made by add- 
ing a soluble carbonate to a soluble calcium salt, as: 
Na a C0 3 +CaCl 2 =2NaCl+ CaC0 3 . 

"-'Green Fire: Barium nitrate, -450. grains; sulphur, 150 grains; potassium 
chlorate, 100 grains, and lampblack, 25 grains. 

t Red Fire: Strontium nitrate, 800 grains; sulphur, 225 grains; potassium 
chlorate, 200 grains, and lampblack, 50 grains. 

For lecture-room experiments the following, without sulphur, are pre 
f erable ; 

Green Fire : Two parts barium nitrate, two parts potassium chlorate, and 
one part ground shellac. 

Red Fire : Two parts strontium nitrate, two parts potassium chlorate, and 
one part ground shellac. 

The ingredients should be dry, powdered separately, and mixed with 
little friction as possible. 



64 



INORGANIC CHEMISTRY. 



The precipitate (CaC0 3 ) may be separated from the CaCl 2 in 
solution, by — 

(a) Filtration — Pouring the mixture into a cone of filter paper 
placed in a funnel, when the water with the dissolved salt will 
pass through, leav- 
ing the insoluble 
portion (the precip- 
itate) on the filter. 
(b) Decantation — Al- 
lowing the precipi- 
tate to settle to the 
bottom, and pouring 
off the clear fluid. 
In either case the 
precipitate may be 
washed from any re- 
maining CaCl 2 by 
adding pure water 
and repeating the 
process. 

Calcium Oxide 
— CaO— Lime, quick 
lime; calx, U. S. P. 




Fig. 58. 



A white solid ; made by heating limestone in rude furnaces called 
kilns. (Fig. 58.) CaC0 3 =CaO+CO a . 

When water is added to CaO there is a violent clfcmical union, 
great heat is evolved, and a hydrate is formed, thus: 

CaO+H 2 0=Ca2HO. 

Calcium Hydrate — Ca2HO — Slaked lime. A white, odorless 
powder; very slightly soluble in water, less than one grain to the 
ounce, but enough to give "lime -water 7 ' {liquor calcis, U. S. P) 
a decidedly alkaline taste and reaction. The presence of sugar 
greatly increases its solubility (liq. calcis saccharatus, Br.). 

Chlorinated Lime — Chloride of lime, bleaching powder, calx 
chlorata, U. S. P. — is a mixture of chloride of calcium (CaCl 2 ) and 
calcium hypochlorite (Ca2C10). It is made by passing chlorine 
gas over slaked lime until it ceases to be absorbed. It is white, 
moistens on exposure to the air, absorbing C0 2 and giving off CI. 



INORGANIC CHEMISTRY. 65 

It is employed as a source from which to get a gradual supply of 
chlorine for disinfecting and bleachin'g purposes. 

Calcium Sulphate — CaS0 4 — occurs native, as gypsum, 
which, when heated, loses its water of crystallization and forms 
a white amorphous powder called plaster of Paris. If this plaster 
be mixed with water enough to form a creamy liquid, it will 
recrystallize or "set" into a hard compact mass. Much used in 
surgery to make casts to hold broken limbs in position. Very 
slightly soluble in water. 

Calcium Phosphate — Ca 3 (P0 4 ) 2 . It is the most abundant 
mineral ingredient of the body; in every tissue and fluid, es- 
pecially the teeth and -bones, to which it gives hardness and 
rigidity. A' white tasteless powder, soluble in dilute acids. Dis- 
solved by lactic acid, it is given as syrupus calcii lactophosphatis, 
U. S. P., in scrofula, rickets, and other diseases of defective nutri- 
tion. 

Calcium 0xALATE^CaC 2 4 , or CaOx — occurs in the juices 
of some plants and in the urine. Obtained as a fine white crys- 
talline powder when a soluble oxalate is added to a calcium 
solution. Insoluble in water or acetic acid, but soluble in the 
mineral acids. 

Hard Waters are such as contain mineral matters, especially 
calcium (lime) compounds. Often water, in passing through the 
soil, becomes highly charged with carbonic acid, and dissolves 
considerable amounts of CaC0 3 , and is hard. This is called tem- 
porary hardness, because on exposure or boiling, the carbonic acid 
is driven off, the CaC0 3 is precipitated, and the water becomes 
soft. The solubility of CaS0 4 does not depend on the presence 
of carbonic acid, and boiling will not precipitate it. So water im- 
pregnated with CaS0 4 is said to be permanently hard. Drinking- 
water should contain a small quantity of lime; but very hard 
water impairs digestion. Hard water is unfit for washing, be- 
cause the soluble alkali soap reacts with the lime salt to form 
an insoluble lime-soap. 

MAGNESIUM. Never free; abundant in magnesian lime- 
stone (CaC0 3 MgC0 3 ). Asbestos, meerschaum, and soapstone are 
native silicates. Most natural waters contain its salts. Silvery 
white metal; burns with a brilliant white light, rich in chem- 
ical rays, and used in photographing caves and other dark places. 



66 INORGANIC CHEMISTRY. 

Magnesium Sulphate — MgS0 4 — occurs in the waters of va- 
rious springs, as those at Epsom ; hence often called Epsom salts. 
Made artificially from the native carbonate, thus: 
MgC0 3 +H 2 S0 4 =MgS0 4 +(H 2 0+C0 2 ). 

White, crystalline, soluble salt of a nauseous bitter taste. It 
is a popular purgative. The nauseous taste and griping may be 
obviated by adding aromatics, acid, sulphate of iron (as in Crab 
Orchard salts), or by free dilution. 

Magnesium Citrate is the most pleasant of the saline purga- 
tives. Usually given as the liquor magnesii citratis, which is pre- 
pared by adding a solution of citric acid to MgC0 3 , and bottling 
immediately to retain the C0 2 . 

Magnesium Carbonate — MgC0 3 — occurs native. For medi- 
cinal purposes it is prepared by precipitation, thus : 

MgS0 4 +Na 2 C0 3 =Na 2 S0 4 +MgC0 3 . 
Similar to chalk in its physical and chemical properties. 

Magnesium Oxide — MgO — Magnesia. Made like CaO, by 
heating the carbonate : 

MgC0 3 =MgO-r-C0 2 . 

Insoluble and tasteless (earthy), but its alkalinity is shown by 
its turning moist red litmus paper blue when the solid MgO is 
dropped upon it. 

Magnesium Hydrate — Mg(H0) 2 . Formed by precipitating 
a magnesium solution with potassium or sodium hydrate. Insol- 
uble in water, but, like other salts of magnesium, soluble in the 
presence of ammonium compounds with which they form double 
salts. Suspended in water, it is called milk of magnesia. 

Magnesium Phosphates. These resemble the calcium phos- 
phates and are associated with them in the body, though in small 
quantity. The ammonio-magnesium phosphate (MgNH 4 P0 4 ) is pre- 
cipitated whenever a soluble phosphate in neutral or alkaline 
solution finds itself in presence of an ammonium salt, as occurs 
in the alkaline fermentation of urine. 

Physiological. Magnesium oxide and hydrate being alkaline 
and tasteless, are popular antidotes for acids. These and the car- 
bonate are given to correct acid conditions of the digestive tract, 
and combining with the acids they form soluble salts that are 
laxative. 



INORGANIC CHEMISTRY. 67 

Analytical. To determine whether a solution be one of barium, 
calcium or magnesium : Add potassium chromate ; a precipitate 
indicates barium. If no precipitate, add ammonium chloride and 
then ammonium carbonate, a precipitate indicates calcium. If 
no precipitate, add sodium phosphate; a precipitate indicates 
magnesium. 

III. Metals of the Earths. 

[Boron B 11] 

Aluminium Al 27 

Scandium Sc 44 

Yttrium Y 92 

Lanthanum La. 139 

Cerium ....Ce 141 

Didymium D 145 

Samarium Sm 1 50 

Erbium E 168 

Ytterbium Yb 173 

Trivalent, though in compounds two atoms go together, form- 
ing a sexivalent radical, as A1 2 C1 6 . Boron is so weakly positive 
that it is a non-metal. (See page 49.) Aluminium is the most 
important member of this group, the others being rare metals 
associated with it in various minerals. Their oxides and hydrates 
are of a neutral or earthy character. 

ALUMINIUM. Never found free, but in the abundance and 
distribution of its compounds it ranks next to oxygen and sili- 
con — third among the elements and first among the metals. Iso- 
lated with difficulty, and therefore costly. Bluish-white metal, 
ductile and very light ; does not tarnish in the air. With copper 
it forms a golden yellow alloy, known as aluminium bronze. 

Aluminium Chloride — A1 2 C1 6 . Prepared industrially in the 
manufacture of aluminium. A soluble, astringent salt. It ab- 
sorbs and combines with H 2 S, PH 3 , and NH 3 . An impure solution 
is sold as a disinfectant under the name chloralum. 

Aluminium Sulphate — A1 2 3S0 4 . Made by treating white 
clay with H 2 S0 4 . It has properties similar to the above. 

Alum — Alumen. An alum is a double sulphate of a trivalent 
and a univalent radical. Its constitution may be expressed thus : 
K^^SO^E^SO,, or 2R I1I E I 2S0 4 . 



68 INORGANIC CHEMISTRY. 

The trivalent radical (E 111 ) may be Al, Fe, Cr, or Mn. The 
univalent radical (E, 1 ) may be K, Na, NH 4 , etc. So, by different 
combinations of these radicals a variety of alums may be formed. 
The old potash alum (A1 2 3S0 4 .K 2 S0 4 ) is giving place in the arts 
to the cheaper ammonium alum (A1 2 3S0 4 . (NH 4 ) 2 S0 4 ). The 'am- 
monio-ferric alum (Fe 2 3S0 4 .(NH 4 ) 2 S0 4 ) is also much used in medi- 
cine. Burnt alum, alumen exsiccatum, is a white amorphous powder 
obtained by heating alum until its water of crystallization is 
driven off. Alum, like other salts in which the acidulous radical 
predominates, is astringent; burnt alum, on account of its avid- 
ity for water, is a mild escharotic. 

Aluminium Silicates. Very abundant, as granite, clay, sand, 
etc. Clay is usually of a reddish or brown color from admixture 
of oxides of Fe, etc. Pure white clay (kaolin) is used in the 
arts to make porcelain, and in medicine as a vehicle for the 
external application of acids, etc. 

CEEIUM is a rare metal. One of its salts, the oxalate, is 
used as a sedative to irritable stomachs, especially in the vom- 
iting of pregnancy. When pure it is a very efficient remedy ; 
but the commercial article is liable to contain salts of lan- 
thanum, didymium, and other allied metals. 

IV. The Zinc Group. 

Zinc, Zn, 65.2, and Cadmium, Cd, 112. 
Bivalent; bluish- white metals, closely allied in sources and 
properties. 

ZINC. When heated in air, zinc burns with an intense bluish- 
white light, forming clouds of oxide. It tarnishes quickly in air 
or water, but becomes coated with a film of oxide that protects 
it from further corrosion. Iron coated with zinc (" galvanized 
iron") will withstand exposure to the weather an indefinite time. 
Alloyed with copper, zinc forms brass. Pure H 2 S0 4 is unaffected 
by pure zinc or zinc coated with mercury (amalgamated), unless 
it form a galvanic circuit.* Commercial zinc is rapidly attacked 
by most acids. 

* Experiment. Into a large test-tube containing bits of zinc pour dilute 
sulphuric acid ; there is a prompt effervescence of hydrogen. Add a little mer- 
cury, and agitate; the action ceases. Drop in a piece of copper; it begins again. 



INORGANIC CHEMISTRY. 69 

Zixc Sulphate— ZnSO A — White Vitriol— is made thus: 
Zn+H 2 S0 4 =ZnS0 4 +H 2 . 
White, soluble salt, resembling MgS0 4 in appearance ; astringent 
and emetic. 

Zixc Chloride — ZnCl 2 . Made: Zn-f 2HCl=ZnCl 2 -f H 2 . A 
white deliquescent salt; strongly astringent; severe caustic. Used 
as an injection to preserve anatomical subjects. 

Zixc Carboxate— ZnC0 3 — is a white, insoluble powder made 
by precipitation: 

ZnS0 4 +*XC0 3 =NaJ50 4 +ZnC0 3 . 

Used in the arts (zinc white) in place of lead carbonate, for it 
is not blackened by H 2 S ; in medicine as a dusting powder for 
excoriated surfaces, and in ointment. 

Zixc Oxide — ZnO — is prepared either 
by burning metallic zinc- or heating the 
carbonate, ZnC0 3 =ZnO+C0 2 . 

It is a yellowish-white powder, used ex- 
ternalhfin ointment, internally as a tonic and 
astringent, especially in the night-sweats of 
phthisis and diarrhea of children. 

Zixc Sulphide — ZnS — is precipitated 
whenever a solution of a zinc salt is added _.^ 
to the solution of a soluble sulphide, unless t:^ ^ 

the solution be acid in reaction. It is the ~ ^ ^z~=?=~mm^ 
only white sulphide, therefore a test for zinc. 1§ " 

Poisoning. All the salts of zinc that are soluble in the digest- 
ive fluids act as irritant poisons. Sodium chloride and organic 
acids dissolve metallic zinc, therefore food kept in galvanized 
iron vessels is more or less poisonous, especially since commercial 
zinc usually contains traces of arsenic. For this reason articles 
intended for toxicological analysis should never be kept in jars 
with zinc caps. 

CADMIUM resembles zinc in its properties and uses, except 
that its sulphide is yellow and insoluble in acid solutions. 

* Experiment. Place bits of zinc in a hessian crucible and heat strongly 
over a triple burner. The metal is volatilized, and the vapor igniting burns 
with an intense bluish-white flame, yielding white flakes of zinc oxide, the 
lana philosophica (philosopher's wool) of the older chemists. (Fig. 59.) 

F 




70 INORGANIC CHEMISTRY. 

V. The Iron Group. 

Chromium Cr 52.2 

Manganese Mn 55.0 

Iron Fe 56.0 

Cobalt Co 58.8 

Nickel Ni 58.8 

These are hard metals and all more or less magnetic. 

By a variation in valence they form two classes of compounds : 
One in which the atom is bivalent, as in ferrous chloride (FeCl 2 ) ; 
the other in which the atom is trivalent, as in ferric chloride 
(Fe 2 Cl 6 ). With oxygen they form acidulous radicals, which form 
the chromates, manganates, and ferrates, with the stronger bases. 

CHROMIUM. So named because all its compounds are col- 
ored. The metal is of but little use. Its compounds are of great 
importance to the chemist and of considerable utility in the arts, 
but few are used in medicine. 

Chromium Trioxide — Cr0 3 — is made by treating a strong 
solution of potassium bichromate with sulphuric acid, thus: 

K 2 Cr 2 7 +H 2 S0 4 =K 2 S0 4 +H 2 Cr0 4 +Cr0 3 . 
The Cr0 3 separates in crimson prisms. It is a powerful oxidant 
and a caustic. Sometimes improperly called chromic acid. 

Chromates. The 
principal ones are po- >r^^^ < ^^^%v N ^) 

tassium chromate, /^^^^ 
K 2 Cr0 4 , a valuable (/;|jK-- 
test reagent, and lead AnM^^^ Jf 

chromate, PbCr0 4 , a € 7 $_ 

yellow pigment. 

Bichromates are 
not regular acid or bi- 
salts, but compounds 
of a chromate and Fig. 60. 

chromium trioxide. The most important of these is potassium 
bichromate, K 2 Cr 2 7 , or K 2 Cr0 4 .Cr0 3 . It forms large red soluble 
crystals. It is added to the sulphuric acid in batteries to oxidize* 
the nascent hydrogen. 

* Experiments. The oxidizing action of the chromic salts can be shown 
in a number of reactions, (a) Any organic substance, as sugar, oxalic acid, or 




INORGANIC CHEMISTRY. 71 

MAXGAXESE resembles iron in its properties. Used to alloy 
iron in the preparation of certain kinds of steel. Its most abun- 
dant ore is the 

Manganese Dioxide — Mn0 2 — Black Oxide of Manganese — an 
insoluble steel-gray powder that readily gives up its extra atom 
of O. Used in large quantities in the preparation of chlorine and 
oxygen gas. 

Manganous Sulphate — MnS0 4 . 

Mn0 2 +H 2 S0 4 =MnS0 4 +H 2 0+0. 
A soluble, rose-colored salt. 

Manganous Sulphide — MnS — is precipitated whenever a 
solution of a. salt of manganese is treated with XH 4 HS. It is the 
only flesh-colored sulphide, hence its formation is a test of man- 
ganese. 

Manganates. If a mixture of KHO. KC1CL and MnCL be 
heated together, there results a green mass of potassium, man- 
ganate, K 2 Mn0 4 . If this be dissolved in distilled water, it forms 
a green 'solution, which, on boiling, or even standing awhile, is 
changed to a purple, due to the formation of potassium perman- 
ganate, K 2 Mn 2 8 . 

The permanganate " gives up its oxygen so readily to organic 
matter, at the same time losing its purple color, that it is used 
as a test for organic impurity in water and as a disinfectant. 

Physiological. Associated with iron (1 to 20), manganese is a 
normal constituent of the blood corpuscles ; hence its prepara- 
tions, like those of iron, are blood tonics. Valuable in amenor- 
rhcea. 

IROX occurs abundantly as oxide, carbonate, and sulphide; 
occasionally free. 

Preparation. The carbonate or sulphide is first roasted until 

a chip of wood, boiled in the sulphuric acid and bichromate mixture, is oxi- 
dized, disappearing completely, with evolution of carbon dioxide, {b) Rinse 
out a beaker with strong alcohol, and then drop in a few crystals of chromic 
acid. The thin layer of alcohol is ignited with the odor of aldehyde, (c) Pour 
a few drops of absolute alcohol on the wick of a spirit lamp (Fig. 60), and lay on 
several crystals of chromic acid. It ignites. 

* Experiment. Powdered potassium permanganate treated with sulphu- 
ric acid gives off ozone. (See page 14.) So powerful an oxidizer is this mixture 
that alcohol, ether, benzol, carbon disulphide, flowers of sulphur, tannin, etc., 
are ignited on contact with it. 



72 



INORGANIC CHEMISTRY. 




converted into oxide. The oxide is heated in a blast furnace 
(Fig. 61) with coal and fluxes (limestone and silicates). The car- 
bon of the coal removes the oxygen 
from the iron, which melts and sinks 
beneath the melted fluxes. The fused 
metal is then drawn off into furrows 
in the sand called pigs. This is cast 
iron, containing 4 or 5 per cent of car- 
bon. Wrought iron contains little or 
no carbon, and steel an intermediate 
amount. 

Properties. A bluish-gray metal, 
sp. gr. 7.5; rusts (oxidizes) when ex- 
posed to moist air, or water contain- 
ing air. 

Fig. 61. Eeduced Iron — Ferrum redactum, 

iron by hydrogen, Quevenne's iron. It is prepared by heating 
ferric oxide nearly to redness in a tube through which hydrogen 
is passed: Fe 2 3 +H 6 =-Fe 2 +3H 2 0. 

It is a very fine, dark gray powder;* prescribed in pill form. 

CHLORIDES. 

Ferrous Chloride— FeCl 2 . Made by adding iron to hydro- 
chloric acid until effervescence ceases, thus: 
Fe+2HCl=FeCl 2 +H 2 . 
Like most ferrous salts, it is green and prone to oxidize with the 
formation of ferric compounds. 

Ferric Chloride — Fe 2 Cl 6 — is made by first forming the fer- 
rous chloride as above, and then adding nitric and hydrochloric 
acids. The nascent chlorine evolved by the nitro-hydrochloric 
acid converts the ferrous into ferric chloride, thus: 

6FeCl 2 +6HCl-f2HN"0 3 =3Fe 2 Cl 6 +N 2 2 -f4H 2 0. 

"Experiments, (a) Reduced iron, if good and fresh, will ignite on con- 
tact with a lighted taper and burn with a red glow, {b) Faraday used to show 
that it is more inflammable than gunpowder, by pouring it mixed with gun- 
powder upon an alcohol flame burning on a white dinner-plate. The iron 
burns with bright scintillations, while the gunpowder falls through the flame 
and is only ignited when the flame dies down and reaches the surface of the 
plate, (c) One part of sulphur, two of reduced iron, and three of nitre make 
an iron gunpowder that burns as quickly and more brilliantly than ordinary- 
gunpowder. 



INORGANIC CHEMISTRY. 73 

' The liq.ferri chloridi, U. S. P, is the aqueous solution. This, 
when diluted with alcohol, forms the tinct.ferri chloridi, U. S. P. 
If citrate of potassium or sodium be added to this tincture, the 
solution loses its styptic taste, does not affect the teeth, and is not 
incompatible with solutions containing tannin. 

SULPHATES. 

Ferrous Sulphate — FeS0 4 — Copperas, Green Vitriol. Pre- 
pared: Fe+H 2 S0 4 =FeS0 4 +H 2 . Soluble, green crystals efflor- 
escing upon exposure. A cheap and excellent disinfectant, de- 
stroying organic matters by abstracting their oxygen. When 
given in pill form it is first exsiccated. 

Ferric Sulphate — Fe 2 3S0 4 — Tersulphate is made by adding 
nitfo-sulphuric acid (HN0 3 H-H 2 S0 4 ) to a solution of the ferrous 
sulphate, thus. 

6FeS0 4 + 3H 2 S0 4 + 2H N0 3 =3Fe 2 3S0 4 +lS T 2 2 + 4H 2 0. 

Its officinal solution is the liq. ferri tersulphatis. Liq. ferri sub- 
sulphatis, U. S. P., Monsel's Solution, is prepared similarly to the 
above, using only half the quantity of sulphuric acid. 

hydrates. 
Ferrous Hydrate — Fe2HO — is precipitated on mixing solu- 
tions of a hydrate and a ferrous salt, as — 

FeS0 4 +2NaHO=:Na 2 So 4 +Fe2HO. 
A green precipitate, which soon oxidizes and becomes brown. 
Ferric Hydrate — Fe 2 6HO. A brownish red, gelatinous mass, 
precipitated by soluble hydrates from ferric solutions, e. g.: 

Fe 2 Cl 6 +6NH 4 HO=6NH 4 Cl+Fe 2 6HO. 

This is the favorite antidote for arsenic, for which purpose it 
must be freshly prepared and given in large doses. Ferric hy- 
drate dissolves freely in a solution of ferric chloride, forming a 
dark red liquid of a styptic taste. 

If this liquid be put in a dialyser (Fig. 62), a vessel with a 
bottom of parchment or animal membrane, and suspended in 
water, the chloride passes out through the membrane into the 
water. When barely enough ferric chloride remains within the 
dialyser to hold the ferric hydrate in solution and the styptic taste 
has disappeared, the liquid is removed and sold under the name 
of "Dialysedlron." 



74 



INORGANIC CHEMISTRY. 



Ferric Nitrate 
Made: Fe 2 6HO+6HNO: 



Fe.6N0 3 . 



=6BLO+Fe 2 6NO-. 



Liq.ferri nitratis, U. 8. P., is a reddish acid liquid. Used as 
an astringent, especially in dysentery. 

Ferrous Iodide — Fel 2 . Prepared: Fe+I 2 =FeI 2 . 
Sometimes given in pill, but better with syrup, which acts as 
a preservative as well as a vehicle. 

Ferrous Carbonate — FeC0 3 — is obtained by adding a solu- 
ble (alkaline) carbonate to a ferrous salt, thus: 
FeS0 4 +K 2 C0 3 -K 2 S0 4 +FeC0 3 . 
It is insoluble in pure water, but slightly soluble in water 
containing carbonic acid, as in chalybeate springs. On exposure 

to the air it turns 
red from formation 
of ferric hydrate ; so 
it is preserved by 
mixing with sugar 
and honey, as in the 
ferri carbonas sacchar- 
atvs, U. S. P. 

Ferrous Sul- 
phide — FeS — occurs 
native, but may be 
made by heating to- 
gether iron filings 
and flowers of sul- 
phur. Used in the 
preparation of H 2 S. 
Scale Compounds 
Flg - 62 - of Iron. These are 

ferric salts, mostly with organic acids. They do not crystallize 
readily, but are sold as thin scales. Made by evaporating their 
solutions to a syrupy consistence, poured upon plates, and when 
dry peeled off in scales. Often other bases, as potassium or am- 
monium, together with alkaloids, as quinine and strychnine, are 
incorporated in the compound. 

The following are officinal: Ferri extras, ferri et ammonii citras, 
ferri et quinice extras, ferri et strychnice citras, ferri et ammonii tartras y 
ferri et potassii tartras, and ferri pyrophosphas. 




INORGANIC CHEMISTRY. 75 

Physiological. Iron is a normal constituent of the body, es- 
pecially the blood corpuscles, where it performs an important 
function, as is shown by the great increase of blood corpuscles 
and of bodily vigor attending its administration. Many of its 
salts, especially the ferric salts of the mineral acids, are astrin- 
gent and hemostatic. Iron is eliminated by various organs, but 
is mainly discharged by the bowels as sulphide blackening the 
faeces. 

Tests for Iron. Ferrous salts are usually green ; with XH 4 HS 
they give a black precipitate of FeS. 

Ferric Salts are usually red; they give a black precipitate 
with NH 4 HS; a black precipitate with tannic acid; and a blood- 
red with sulphocyanate of potassium. 

COBALT. Its chief ore is a compound with arsenic, sold un- 
der the name of cobalt or fly stone, for poisoning flies. Its salts are 
used in preparing sympathetic ink, for when free from moisture 
they are deep blue, but almost colorless when moist. Writing 
done with a dilute solution of chloride of cobalt is invisible until 
warmed, when it becomes blue, the color disappearing when the 
paper is cooled or moistened. 

Test for Cobalt. It imparts a deep blue color to a bead of glass 
or borax melted in the blow-pipe flame. 

NICKEL. This is a hard, grayish-white metal that does not 
tarnish in the air. Used to electro-plate instruments made of 
metals more prone to corrode, and to make cheap coin. Mixed 
with brass, it forms German silver. 

VI. The Lead Group.* 

Tin (Stannum) ; Sn 118 

Lead {Plumbum) Pb 207 

The members of this group are bivalent and quadrivalent. 

TIN. A bluish-white malleable metal, not corroded by air 
or water; hence used to form a protective coating for iron and 
copper. Tin-ware is usually sheet-iron coated by being dipped 

-This is really a continuation of the Carbon Group, the metallic character 

increasing with the atomic weights: C=12; Si=28; =73; Sn=118; Pb=207. 

The third member, corresponding to arsenic of the Nitrogen Group, is yet un- 
discovered. 



76 INORGANIC CHEMISTRY. 

into molten tin. Tin alloyed with lead is easily dissolved, and 
may cause lead-poisoning. 

Tin-foil (thin laminae of tin) is used in wrapping to exclude 
air and moisture. Tin enters into the composition of a great 
many alloys. Powdered tin is sometimes used as an anthelmintic. 

Tin forms two classes of compounds ; the stannous, in which 
the atom is bivalent, and stannic, in which the atom is quadri- 
valent. These are of importance to the chemist, but of little 
interest to the physician. 

LEAD. Its principal ore is its sulphide (PbS), called galena. 
It is a soft, heavy, blue metal, very slowly acted upon by most 
substances ; hence used to make water-pipes and vessels that are 
exposed to corrosive liquids. 

Water containing nitrates or nitrites (from organic matter) 
dissolves lead slightly; but if it contains carbonates or sulphates, 
the lead is protected by an insoluble coating of lead carbonate 
or sulphate. 

Lead enters into the composition of many alloys ; as pewter, 
solder, shot, type-metal, etc. The quadrivalent compounds of 
lead are of so little importance that the term plumbic is applied 
to the bivalent compounds. 

Lead Oxide — PbO — Litharge. A yellow substance, found na- 
tive ; made artificially by heating lead in the air. It is by treat- 
ing this with the appropriate acid that most of the lead salts are 
prepared. When rubbed with oils it decomposes the glyceryllic 
ethers and combines with the fatty acids to form lead soaps, one 
of which, the oleate, is lead plaster, emplastrum plumbi, U. S. P. 

Lead Dioxide, or puce lead, is a dark brown powder, forming 
one of the constituents of red lead (Pb 3 4 or 2PbO Pb0 2 ). 

Prepared by treating red lead with nitric acid to dissolve out 
the PbO. 

Lead Nitrate — Pb2N0 3 . 

Made: PbO+2HN0 3 =Pb2N0 3 +H 2 0. 

Ledoyerils disinfectant fluid is a solution of Pb2N0 3 (one dram 
to the ounce). It corrects fetid odors by neutralizing H 2 S and 
NH 4 HS. 

Lead Acetate — Pb(C 2 H 3 2 ) 2 , or PbAc 2 — Sugar of Lead^ 

Made: PbO+2HAc-=PbAc 2 +H 2 0. 



INORGANIC CHEMISTRY. 77 

Used in medicine more than any other lead salt. Its solution 
will dissolve considerable quantities of PbO, forming the solu- 
tion of the subacetate of lead, the liquor plumbi subacetatis, U. S. P., 
Goulard's extract. It is astringent, and, like all the lead salts, 
sedative. Much used as a topical application in erysipelas, acute 
eczema, and other skin affections ; and diluted {lead-water), it is 
used in conjunctivitis and other mucous inflammations. 

The following insoluble satts may be made by precipitation 
from solutions of the preceding soluble ones : 

Lead Chloride — PbCl 2 . Made: Soluble lead salt added to 
a soluble chloride; e. g. PbAc 2 +2HCl=PbCl 2 +2HAc. Slightly 
soluble in warm water, but in cold it is always precipitated from 
solutions of moderate strength ; hence classed with HgCl and 
AgCl as one of the three insoluble chlorides. 

Lead Sulphate — PbS0 4 . Forms as a white precipitate when- 
ever a solution of a lead salt is added to a sulphate solution, thus : 

PbAc 2 +ZnS0 4 =PbS0 4 +ZnAc 2 . 

Lead Carbonate — PbC0 3 — White Lead. 

Made : PbAc 2 +Na 2 C0 3 =rPbC0 3 -f 2Xa Ac. 

Commercially, it is made by some modification of the old 
Dutch method, which consists in covering bars of lead with the 
refuse of the wine-press and barn manure. The acetic fumes 
from the grape husks attack the lead, forming lead acetate, which 
is decomposed by the carbonic acid from the manure. The acetic 
acid thus liberated combines with another portion of lead, which 
is again precipitated by the carbonic acid, and thus the process 
continues until all the lead is consumed. 

Used for painting, but blackens when air contains H 2 S. 

Lead Sulphide — PbS — is formed as a black precipitate when- 
ever a lead solution is treated with a soluble sulphide, as H 2 S or 
NH 4 HS. 

Lead Iodide — Pbl 2 . A bright yellow precipitate on adding 
a soluble iodide to a lead solution; as, 

PbAc 2 +2KI=2KAc+PbI 2 . 

Lead Chromate— PbCr() 4 . 

Made: PbAc 2 +K 2 Cr0 4 =PbCr0 4 -f 2KAc. 

Under the name of chrome yellow it is used in painting. Of 
late it has been used to color food products. 



78 INORGANIC CHEMISTRY. 

Tests for lead consist in forming precipitates of the foregoing 
insoluble compounds. 

Physiological. All the lead compounds are poisonous. Acute 
poisoning sometimes occurs from the ingestion of a single large 
dose of a soluble lead salt. The symptoms are those of gastric 
irritation. Treatment. Give MgS0 4 to form the insoluble PbS0 4 . 

The chronic form of lead intoxication, painter's colic, is purely 
poisonous, and is produced by trie continued absorption of mi- 
nute quantities of lead by the skin of those handling it, and by 
the lungs and stomachs of those living in painted apartments, or 
using food and drink from leaden vessels. There is impairment 
of digestion, constipation, blue line along the edge of the gums, 
colic, and paralysis, especially of the extensor muscles. Lead 
once absorbed is eliminated very slowly, having combined with 
the albuminoids, a combination which is rendered soluble by the 
administration of iodide of potassium. 

The treatment for chronic lead-poisoning is to give MgS0 4 , for 
the double purpose of overcoming the constipation and precipi- 
tating any lead remaining unabsorbed in the alimentary canal ; 
also KI to promote the elimination of that which is combined 
with the albuminoids. Alum is a favorite treatment, seeming to 
perform all accomplished by both the MgS0 4 and KI. The para- 
lyzed muscles must be treated with electricity, so that when the 
lead is eliminated and the nerve influence returns, it may not find 
them degenerated past redemption. 

VII. The Copper Group. 

Copper {Cuprum) Cu 63.4 

Mercury {Hydrargyrum). ..Hg 200 

Each of these elements is univalent and bivalent, forming two 
classes of compounds, " ous" and t( i&" At ordinary temperatures 
they are acted upon but slowly by the non-oxidizing acids, as 
H 2 S0 4 and HC1 ; but HN0 3 attacks them vigorously. 

COPPER is usually found combined with sulphur, etc., but 
often in the metallic state, especially on the southern shores of 
Lake Superior. Being found free, it was among the first metals 
wrought by man, so the bronze preceded the iron age. Copper is 
a red malleable metal ; an excellent conductor of electricity. 



INORGANIC CHEMISTRY. 79 

Cupric Sulphate — CuSO, — Blue Vitriol, Blue Stone. Obtained 
as an incidental product from silver refineries, copper mines, 
etc.; made experimentally by heating copper with strong H 2 S0 4 . 
Forms beautiful blue crystals, soluble in water, but insoluble in 
alcohol. If the crystals be heated they lose their water of crys- 
tallization and form a white powder, which becomes blue again 
upon the addition of water. Hence, used as a test for water in 
alcohol. Like other salts in which the acidulous radical predomi- 
nates, cupric sulphate is astringent and coagulates albumen. A 
prompt emetic, but not used as much as ZnS0 4 , because if, by 
chance, it be not all ejected from the stomach, a gastro-enteritis 
is liable to be set up. 

Cupric Hydrate — Cu2HO — is formed as a bluish-white pre- 
cipitate whenever a soluble copper salt is treated with a soluble 
hydrate, thus: CuS0 4 +2KHO=K 2 S0 4 +Cu2HO. 

When heated, even under water, it decomposes — 
Cu2HO=CuO+H 2 0. 

Cupric Oxide — CuO — Black Oxide. Prepared by heating cop- 
per turnings in air. It gives up its oxygen easily, hence used as 
an oxidizer in organic analysis. 

Cuprous Oxide — Cu 2 — Suboxide. Made by boiling the 
cupric oxide with an oxidizable substance, as glucose (copper 
tests for glucose), which is oxidized at the expense of the oxy- 
gen of the cupric oxide. The precipitate is first yellow (hy- 
drate), but soon becomes a bright red (oxide). 

Cupric Subacetate or Ox y acetate — sometimes called ver- 
digris (green-gray) — is made industrially by exposing plates of 
copper to the acetic fumes of grape husks, etc. It is apt to be 
formed whenever fruits containing acetic acid are placed in cop- 
per vessels. 

Tests. 1. Plating Test. Dip into the suspected solution a more 
electro-positive metal, as iron, and a plating of metallic copper 
will be deposited on the iron, an equivalent proportion of which 
takes the place of the copper in the solution. 

2. Sulphur Test. Add H 2 S or NH 4 HS, and if copper be pres- 
ent a black precipitate (CuS) will be formed. 

3. Ammonia Test. Add ammonia, and if copper be present a 
deep blue ammonio-salt of copper will be formed. 



80 INORGANIC CHEMISTRY. 

4. Arsenic Test. To the ammonio-salt, described above, add 
an aqueous solution of As 2 3 , and a green precipitate of arsenite 
of copper (pans green) will be thrown down. 

5. Glucose Test. Add KHO, (CuS0 4 +2KHO=K 3 S0 4 +Cu2HO) 
and boil (Cu2HO=CuO+H 2 0), with a little glucose, and a yel- 
lowish-red precipitate (Cu 2 0) indicates copper. 

It will be seen from the two last reactions, above described, 
that a substance acted upon characteristically by a reagent is as 
good a test for the reagent as .the reagent is for it — i. e. arsenic 
and glucose, being acted upon characteristically by copper, are as 
good tests for copper as copper is for them. 

Physiological. Canned fruits, pickles, etc., that have been col- 
ored green with copper, and food, especially if acid, that has been 
cooked or kept in copper vessels, are apt to give an acute gastro- 
enteritis. Chronic copper poisoning, so called, is perhaps always 
due to other substances, as lead or arsenic, and should be treated 
accordingly. 

Antidotes for acute copper poisoning: Encourage vomiting and 
give albumen (white of egg), which combines witl\ the copper 
salt to form an insoluble albuminate; or iron filings, which will 
precipitate the copper in metallic state. 

MERCURY is the only metal liqui.d at ordinary temperatures, 
and resembles silver in appearance, hence the names hydrargy- 
rum (water silver) and quicksilver 
(fluid silver). It is so heavy that 
iron and stone float upon it as corks 
on water. (Fig. 63 represents a mar- 
ble and a ball of iron floating on e|j!l 
mercury.) It does not tarnish in 
the air unless contaminated with 
baser metals; dissolves all metals, 
except iron, to form amalgams. 

Uses. Metallic mercury is used extensively in the refining of 
silver and gold, in thermometers and other instruments, with tin 
in silvering mirrors, and in many other branches of the arts. 
Metallic mercury, rubbed up with various excipients until glo- 
bules cease to be visible, forms several officinal preparations. 
Rubbed with chalk it forms "gray powder," hydrargyrum cum 
creta; with confection of roses and licorice powder it forms 




INORGANIC CHEMISTRY. 81 

"blue pill," pilula hydrargyri; and with lard and suet it forms 
"mercurial ointment," unguentum hydrargyri. The therapeutic 

activity of these preparations ia not due to the metallic mercury 
they contain, but to small quantities of mercurous oxide formed 
by the oxidation of the finely divided metal. So their strength 
varies with the thoroughness of the rubbing, the extent of the 
exposure, and the age of the preparation. 

Mercurous Iodide — Hgl — Profo-iodide. Green Iodide. Hydrar- 
gyri Todidum Viride. U. B. P Made by rubbing together chemical 
equivalents of mercur - and iodine (127) until they com- 
bine and form a green mass. 

Mercuric Iodide — Hgl 2 — Biniodide, Red Ic jyri 

Rubrum. Made like the above, except that two equiva- 
lent- ed. 

B >th the iodides, being insoluble may be precipitated by add- 
ing a . of KI t tion of mercurous salt for the one 
and a mercuric for the other, thus: 

HgN0 3 +KI:=HgI+KN0 3 and 
Hg2N0 3 +2KI=HgI 2 +2KN0 3 . 
The mercuric i 3S of either the 

Hg2N0 3 or the KI. In preci _. mercuric iodide i- first 

yelluw, but rapidly becomes red. If - >me of the dry red 
der be placed on a sheet of paper and warmed over a lamp, it 
changes back to yellow, but on -baking or rubbing the red is 
red. These changes in color are due to changes in crystal- 
line structure. 

Mercurous Xitrate — HgN0 3 — is formed when mercury is 
treated with cold dilute nitric acid. 

Mercuric Nitrate — Hg2X0 3 . — Acid nitrate of . is 

formed if the mercury be boiled with strung nitric acid. Like 
all nitrites, both of the above are soluble. It enters into the liq. 
troti*! U. S. P., and "citrine ointment," way. hydrar- 
gyri nitratiSj U. S. P. 

Mercurous Sulphate — Hg.SO. — is made by digesting buI- 
phuric acid with excess of mercury. 

Mercuric Sulphate — H_>0_ — is made by heating mercury 
with excess of sulphuric acid. A white, crystalline salt, used in 
some forms of galvanic batteries. When diluted with water it 
decomposes into an acid salt, which remains in solution, and a 



82 INORGANIC CHEMISTRY. 

yellow precipitate of oxysulpbate, HgS0 4 .2HgO, called "turpeth 
mineral," hydrargyri subsulphas flavus, U. S. P. 

Mercurous Chloride — HgCl — Calomel, mild chloride, Hydrar- 
gyri Chloridum Mite, U. S. P. — is made by heating mercurous sul- 
phate with sodium chloride (Hg 2 S0 4 +2NaCl=NaJ30 4 +2HgCl), 
when the mercurous chloride sublimes and is condensed in a 
cool receiver. 

Calomel is a white, insoluble powder. Exposed to light it is 
slowly decomposed (2HgCl==Hg-j-HgCl 2 ). With aqua regia, and 
more slowly with other soluble chlorides, it is converted into mer- 
curic chloride. Calomel probably passes through the stomach 
unaltered, but is converted into the mercurous oxide by the 
alkaline fluids in the small intestine. 

Mercuric Chloride — HgCl 2 — Bichloride of Mercury, Corrosive 
Sublimate — is prepared by sublimation from a mixture of mer- 
curic sulphate and sodium chloride, thus: 

HgS0 4 +2NaCl-]S T a 2 S0 4 +HgCl 2 . 

It is crystalline and soluble, with a disagreeable styptic taste, 
and is very poisonous. 

Mercuric Ammonium Chloride — Ammoniated Mercury, White 
Precipitate, U. S. P. Formed by adding ammonia to a solution of 
mercuric chloride; mostly used in ointment. It is a double salt 
of mercury and NH 2 a derivative of ammonium. Its composi- 
tion is that of NH 4 C1, in which two atoms of H are displaced by 
one of Hg, forming NH 2 HgCl. The ammonio-sulphate of copper 
previously described has an analogous composition. 

Mercurous Oxide — Hg 2 — Black Oxide of Mercury — is made 
by treating a mercurous salt with a soluble hydrate, as: 
2HgCl+2KHO-Hg 2 0+2KCl+H 2 0. 

It is seldom used in medicine. 

Mercuric Oxide — HgO— Bed or Yellow Oxide. When pre- 
pared by decomposing mercuric nitrate by heat, it is crystalline 
and of a red color {hydrargyri oxidum rubrum, U. S. P.) ; but when 
made by precipitating a mercuric solution with a hydrate, 

HgCl 2 +2KHO=HgO-h2KCl+H 2 0, 
it is an amorphous yellow powder {hydrargyri oxidum flavum, 
U. S. P.). The yellow variety, being amorphous and more finely 
divided, is less gritty and has greater therapeutic activity. 



INORGANIC CHEMISTRY. 83 

Oleate of Mercury is made by warming the yellow oxide 
with oleic acid. A liquid or semi-solid. Applied to the skin it 
is rapidly absorbed. 

Mercurous Sulphide — Hg 2 S — is an unstable compound, 
which falls as a black precipitate when a mercurous solution 
is treated with a soluble sulphide. 

Mercuric Sulphide — HgS — falls as a black precipitate when 
a mercuric solution is treated with a soluble sulphide. It is 
found in nature in crystalline masses called cinnabar. By certain 
processes it may be obtained as a deep-red crystalline powder, 
called vermilion. 

Tests. These consist in adding to the suspected liquid solu- 
tions of salts containing radicals capable of uniting with mercury 
and forming precipitates of the foregoing insoluble compounds. 
But the galvanic test is perhaps the best for clinical purposes. On 
a gold or copper coin put a drop of the suspected solution acidu- 
lated with HC1, and with a piece of baser metal, as a knife blade, 
touch the coin through the drop of fluid. Mercury, if present, 
will be deposited on the coin in a silvery film. 

Physiological. Acute poisoning occurs from swallowing a sin- 
gle large dose of some of the mercuric compounds, especially 
corrosive sublimate. The minimum fatal dose of corrosive sub- 
limate is three grains; of white precipitate and turpeth mineral 
forty grains. Children tolerate mercury much better in propor- 
tion to their age than adults. The symptoms are those of severe 
gastro-enteric irritation. Give albumen, with which it forms an 
insoluble compound. Iron filings also act as a chemical antidote 
by decomposing the salt, taking the acidulous radical and depos- 
iting the mercury in the metallic state. 

Chronic poisoning is often called from its most prominent 
symptom, salivation or ptyalism. It usually occurs from small, 
but often repeated doses of the mercurous preparations, as blue 
pill, calomel, etc, One of the first symptoms is a delicate red line 
along the margin of the gums, then comes a metallic taste, ab- 
dominal pains, nausea, vomiting, dysenteric-diarrhea, profuse flow 
of saliva, fetid breath, fever, emaciation, and paralysis. Sphace- 
lation of the mouth and lips sometimes occurs. The treatment 
is to stop the ingestion of poison, and give some astringent, as 
tannin. 



84 INORGANIC CHEMISTRY. 

VIII. The Silver Group. 

Silver (Argentum) Ag 108 

Gold (Aurum) Au 197 

Platinum Pt 197.4 

These are heavy, bright metals, not easily corroded, rare and 
very valuable. Silver is univalent; gold, trivalent; and plati- 
num, quadrivalent. 

SILVER occurs free, but oftener as a sulphide associated with 
lead in galena. A white, malleable, ductile metal, capable of a 
high polish ; best known conductor of electricity; dissolved read- 
ily by nitric, but not by hydrochloric or sulphuric acid, except 
by the aid of heat; does not tarnish in air unless ozone or H 2 S 
be present. 

Used to plate mirrors and articles made of the more corrodible 
metals ; alloyed with copper as coin ; for tubes, sutures, etc., in 
surgery, for it does not corrode and irritate the tissues. 

Silver Nitrate — AgN0 3 — Argen ti Nifras, U. S. P., Lunar 
Caustic. Made by the action of nitric acid on silver. If coin 
silver be used, the solution is blue from the presence of copper. 
Silver nitrate is a crystalline salt, very soluble. Its taste is acrid, 
and in large doses it acts as a corrosive poison, destroying the 
tissues by coagulating their albumen. For use as a cautery it is 
fused and molded into sticks. 

Sllver Oxide — Ag 2 — is precipitated as a brown powder on 
treating a solution of silver nitrate with caustic potash or soda 
(2AgN0 3 +2KHO=2KN0 3 +Ag 2 0+H 2 0). Slightly soluble in 
water. The other salts of silver are insoluble, and made by pre- 
cipitating a solution of silver nitrate with a solution containing 
the appropriate radical. 

Silver Cyanide — AgCN. 

AgN0 3 +KON=AgCN+KN0 3 . 

White precipitate, soluble in ammonium hydrate. 

Silver Chloride — AgCl.* 

AgN0 3 +NaCl=AgCl+NaN0 3 . 

White precipitate; insoluble in nitric acid, but freely soluble 
in ammonium hydrate. 

-There are three insoluble chlorides, viz., PbCb, HgCl, and AgCl. They 
may be distinguished by ammonia, which dissolves AgCl; blackens HgCl, and 
has no effect on PbCb. 



INORGANIC CHEMISTRY. 85 

Silver Bromide — AgBr. 

AgN0 3 +KBr=AgBr+KN0 3 . 
Yellowish-white precipitate; slightly soluble in ammonium 
hydrate. 

Silver Iodide — Agl. 

• AgN0 3 +KI=AgI+KN0 3 . 

Yellow precipitate ; insoluble in ammonium hydrate. 

Effects of Light Light decomposes salts of silver, especially 
if organic matter be present, depositing metallic silver in a fine, 
black powder, hence their uses in photography, and in making 
indelible inks, hair dyes, etc. The black stain of silver on the 
hands or clothes may be removed by potassium cyanide or by 
applying tincture of iodine and washing in ammonia- water. 
When persons have taken silver salts for a long time, it some- 
times occurs that the tissues, especially the skin, are perma- 
nently darkened. This is due to the decomposition of the silver 
salt under the influence of organic matter and light. 

Poisoning occurs mostly from swallowing the nitrate, which 
is the only soluble silver salt. It is a severe corrosive poison, 
destroying the tissues by coagulating their albumen. Its best 
antidote is a soluble chloride, as common salt, which forms the 
insoluble silver chloride. Albumen is also a good antidote. 

GOLD occurs widely, but sparingly distributed ; always free, 
mixed with sand and quartz, from which it is separated by agi- 
tation with water or by dissolving it out with mercury. It is a 
soft, bright, yellow metal; so malleable that it may be beaten 
into sheets (gold-leaf) less than one two-hundred-thousandth of 
an inch in thickness. These transmit green light. For coinage 
and general use gold is usually hardened by the addition of cop- 
per or silver, the amount of which is indicated by the term carat 
fine. Thus, pure gold is twenty-four carat, and eighteen, six- 
teen, and twelve carat signify so many twenty-fourths of pure 
gold. 

Gold does not tarnish in the air ; is unaffected by any single 
acid, but nitro-muriatic acid (aqua regia) easily dissolves it, form- 
ing auric chloride, AuCl 3 , a caustic salt, which is sometimes given 
as a nerve tonic and aphrodisiac. Dose, one twentieth to one tenth 
of a grain. 

G 



86 INORGANIC CHEMISTRY. 

PLATINUM occurs free, associated with the allied metals, 
palladium, rhodium, rhuthinium, and iridium. Owing to its 
scarcity it is almost as costly as gold. Resembles silver in ap- 
pearance; can be melted only with great difficulty, and very few 
substances corrode it; hence it is used to make vessels that are 
to be exposed to high temperatures, or to contain corrosive chem- 
icals. Platinum wire is also used in flame-testing. 

Platinum readily dissolves in nitro-muriatic acid, forming pla- 
tinic chloride, PtCl 4 , a valuable reagent for potassium, ammonium, 
and alkaloids. 



INORGANIC CHEMISTRY. 



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;__.^— — ~ +3 Id — i -»-> x O 

Pfm s *-— to — pq d •- jh 






w g £ — ' +i • . r -~ "Z d 












O K^^CDffldS 






u 




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^ > o 
R J o 

£ QQ < 

*2§ 
a « & 

g2g 
q o ; 

■ 7l rS. 



pqft 



o ,rH 


Nitrates. 
Chlorates. 

Apply spe- 
c i a 1 tests. 
(See previ- 
ous pages.) 


00 



5 

& 


u 

ft 

VO 

6 


Phosphate^ y e ^]™ h - 

Borates, yellowish. 
Oxalates, yellow. 
Carbonates, reddish. 
Acetates, red if neutral. 
Sulphides, black. 




1 




Pi 

ro 

O 

<1 


■ white. 

llowish- 
white. 

yellow. 

ick. 

n dilute 

except 

)mide, 

de, and 


Borates 

Carbonates 

Chlorides 

Citrates 

Cyanides 

Oxalates 

Sulphates 

Tartrates 

Bromides] ^ e 

Iodides ) 
Phosphates j 
Sulphides, bh 

All soluble i 
nitric acid, 
chloride, br< 
iodide, cyani 
sulphide. 


CC 
O 



Fh 
N 


(All white.) 
Sulphates, sol. in much 

water. 
Borates ) soluble in 
Carbonates y^pf m 
Citrates J WM4U 
Phosphates. 
Oxalates. 
Sulphites. 
Tartrates. 

All sol. in acetic acid, 
except oxalate and some 
sulphate and tartrate. 
All sol. in HCl, except 
much sulphate. Citrate 
and tartrate char when 
heated on platinum foil. 
Carbonate and sulphite 
effervesce with acids, 
evolving H2S and SO2. 


CC 

ft 

ft 

N 

O 

w 


S r-H fc ."S U +> ^ 

^ ,rH ojO-^ ft w 

r-l of G> Si ^ ' S 

<%2t OB'S rijff 

3 S c3 -M b O XXj 
0205O ^g MOPh 


p 

C 
ft 

c 



'C 
"<*■ 
C 
02 


With effer- 
vescence of 
H2SandS0.2 
known by 

'smell, and 
CO2 having 
no noticea- 
ble odor. 

with odor of 

with odor of 
icetic acid, 
especially if 
warmed. 


Sulphides 
Sulphites 
Carbonates 

Cyanides ■! 

f: 

Acetates ■< J 



S4S - N < 

H R 

o o 



o 





* 






pi 












o 












-2 




« 


- 




w 


n 




H 


DO 




<J 







£ 






g 


o 


+a 


i— i 


+a 




m 


fl 


fi 


H 


£ 




k4 





C 


< 


Pi 


Pi 


x 


M 


BR 


£h 


s. 


01 

C 


G 


0? 


-3 




DO 


Fh 


fH 


5- 


O 


3 


o 

p! 


3 
► 


H 


n 


U 


8 




PI 


P 


pa 


Pi 
Pi 


o 


o 


X 





c- 


H^ 





CD 


P4 


CU 


~E 


o 


tf 


pi 


> 


od 





H 




pi 


M 






^ 


q 




M 




>— 


pq 


m 


.~ 


P 


CD 




O 


i — i 


= 


QQ 


ti 





K 


CJ 


QQ 


w 


P, 


k» 


E-" 


-r 


— 


1 


d 


:jl 


H 


>, 


to 


H 

H 


p. 


on 




ACQ 


w 


cS 




Hi 


o 




pq 


Pi 





« 



eg 



p 
s 



Tartrate. 



Sulphite. 


02 02 02 QQ 02 W 


Sulphide. 


HODHffiHHffiHHHHHHH^HHHHHMHOQHHCOH 


Sulphate. 


CCQQHHHHCOOQKMCOaODCC^.MOOCQCOCWCQaiCC^OQCCajl-iCQ 


Phosphate. 


— X — — — — — — — — — — -- — — — — — —:-. X — X — — — — 


Oxide. 


03 

Hf-HDQHHSOHHHHHHHHHHHHHWHJBHHDQH 


Oxalate. 


^CCCOl^^HHHHCOMHHQCCQc-.^M|^l--lhHI-H5-.aQt-lQQQC(-HMI-H 


Nitrate. 


CQOQe-.OQCOa3CaaQGQCQXOQe-.aDaOaDaDGQ'X)CQ3QCQQQGQaQQQaQ 


Iodide. 


c-.CO(-lCCi-iCCC»CQ3Q jaQCOwXGQXHHMMOiGQt-HGCCGGQGQGQ 


Hydrate. 


02 02 
H-tffi HCCHHO3HHWHHHXHHHC-HMQDe-a3HH0[e- 


Cyanide. 


^aQ^CQ^r.MHHM^HHHr.HCQe-He-CQHCCe-e-CQH 


Chromate. 


HHXlf-f^Hi-ie-COi-ic-. X GO e- e-hHQQCQaJt-ii-(e-.Mi-iQQ)-ii-Hi-HCQ 


Citrate. 


CQOJc-.OQCOX!X'CQCQiZ!CC75 c --CGCCi-lc-.i-iCOe- QQ(-(QQc-c-i-iCQ 


Chloride. 


OQGQXGQCOGGXXXXXXXXXXX^tBaGGG^CGaQGQGQCC 


Carbonate. 


t— 1 CC CN« H- 1 t— ( I— I.I— 1 KHI-HI— (C- h- (C- 1— II— IH- It— Ih-fl— IC-CQl— lX<C^<>-l— (1— « 


Arsenite. 


HfflHH^ fr .HNHHMH^HHe-HHM^ODHODHHMN 


Arseniate. 


HOQHHH^HHHHHHHHHHHHHHOQHQQC-HHH 


Acetate. 


COQQCCX!CQGQCCaQMCQCOaQ^C03QCQCOCOCC^CQ^CQCOOQCQCC 



3-3 & 






go 



^ PS 

o?3 



-<<J<JmSu03uu^^iOi^SSSS^SSJaaQMSaQN 



OEGA^IO CHEMISTET. 



Formerly organic chemistry was defined as the chemistry of 
the compounds produced only by organized life. Gradually this 
definition has been abandoned, for with the increase of chemical 
knowledge many substances identical with the animal and vege- 
table products have of late years been made in the laboratory 
without the aid of the vital force, and probably, if their chemical 
constitution were fully understood, all animal and vegetable 
products could be duplicated artificially. However, chemistry 
has not, and probably never will, produce an organized body ; i. e., 
one having an anatomical cellular structure. 

# It is a noticeable fact that every organic compound contains 
carbon. Hence, organic chemistry is now defined to be " the chem- 
istry of the carbon com pounds," and the following pages may be 
considered a resumption of the study of that element. 

Though carbon forms compounds of infinite number and ex- 
treme complexity, it is with the aid of a very few other elements, 
viz., hydrogen, oxygen, nitrogen, and occasionally sulphur, phos- 
phorus, and iron — sometimes others; but the larger number of 
even the artificial compounds contain only the above-named ele- 
ments. This is due to the fact that the carbon atoms possess in 
the highest degree the power of combining with each other and inter- 
changing valences, forming groups or chains around which the other 
elements are arranged. But for this power carbon could form 
only one saturated compound with hydrogen, CH 4 . Carbon being 
quadrivalent, the compounds C 2 H 6 and C 3 H 8 would be unsatu- 
rated. Experiment, however, proves that they are saturated com- 
pounds. The explanation is that the carbon atoms combine with 
each other, mutually neutralizing one or more valences, thus: 

H H H H H H 

H— C— H; H— C— C— H; H— C— C— C— H. 



H H H H H H 



ORGANIC CHEMISTRY. 91 

It will be observed that these formulae have a common differ- 
ence of CH 2 . They are said to form a homologous series. When 
the carbon remains the same but the hydrogen differs by H 2 , the 
series is said to be isologous. 

In the following examples each vertical .column represents a 
homologous, each horizontal line an isologous series : 



CH 4 


CH 2 


C 


C 2 H 6 


C 2 H 4 


C 2 H 2 


C 3 H 8 


C 3 H 6 


c 3 n 4 


C 4 H I0 


C 4 H 8 


C 4 H 6 


C 5 H I2 


C 5 H I0 


C 5 H 8 



etc. etc. etc. 

Without this arrangement in series, it would be impossible to 
remember the composition of organic substances. 

Hydrocarbons are compounds of carbon with hydrogen. Of 
these CH 4 is the type from which all the other members of this 
class may be regarded as derived in isologous or homologous series. 
Petroleum is a mixture of the homologous derivatives from the 
first (CH 4 ) to about the sixteenth (C l6 H 34 ). These are separated 
by distilling the crude oil. Those having the smallest molecules, 
being lightest, pass over first, forming naphtha, benzine, etc. As 
the heat is increased the medium-weight compounds come over 
next, forming kerosene. The residuum consists of the heaviest 
carbohydrides, which can be distilled only by high heat, forming 
lubricating oil, vaseline, paraffine, etc. Kerosene is the one used for 
ordinary lamps. If it contains too much of the lighter products 
it is liable to give off vapors which, mixing with air, are explo- 
sive. In most States it is illegal to sell kerosene which gives off 
an inflammable vapor (" flashes") below 100° F. 

The Volatile Oils are a class of carbohydrides, all having 
the same formula, C I0 H l6 . Though having very different chemical 
and physical properties, they are composed of the same elements 
in the same proportion. Such bodies are said to be isomeric {Ivog, 
equal, //epoc, part). 

Volatile oils are found in plants, especially the flowers, of 
which they are usually the odorous essences (hence called also 
essential oils). Obtained by distillation from flowers, etc. Very 
slightly soluble in water (aquce), but quite soluble in alcohol {spir- 



92 ORGANIC CHEMISTRY. 

itus). A cologne is an alcoholic solution of an assortment of vol- 
atile oils. A large number of volatile oils are officinal ; as. anise, 
bergamot, cinnamon, lemon, orange, wintergreen, etc. 

Turpentine {oleum terebinthince, U. S. P.) may be taken as a type 
of the class. It is <x thin, colorless liquid, a valuable solvent of 
oils and resins; absorbs oxygen and stores it up as ozone, gaining 
thereby oxidizing, antiseptic, and disinfectant properties. By the 
action of concentrated sulphuric acid, turpentine is changed into 
terebene (C I0 H l6 ),'a valuable remedy for bronchitis and flatulence. 
On exposure to the air the volatile oils oxidize with production 
of resins and camphors. 

Resins are formed by the oxidation of volatile oils. Insol- 
uble in water; soluble in alcohol and ether; alkalies dissolve 
them, forming soapy mixtures. The officinal resin (resina, U. S. 
P.) is formed by the oxidation of turpentine as it exudes from 
the pine tree. 

In the natural state resins are usually mixed with other sub- 
stances. Mixed with volatile oils they form oleo-resins and balsams, 
e. g., benzoin, tolu, and balsam of Peru, and with gums, gum-resins, 
e. g., ammoniac myrrh and asafcetida. 

Camphors. Common camphor, obtained from the camphor 
laurel, is a white, crystalline, volatile solid of a peculiar pun- 
gent odor; slightly soluble in water (aqua camphorce, U. S. P.), 
and freely soluble in alcohol and ether. 

Monobromated camphor, used in medicine as a sedative, is formed 
by substituting one atom of bromine for one of hydrogen in ordi- 
nary camphor. 

Menthol is a camphor-like body found in oil of peppermint, 
and possesses the odor of that plant. 

Caoutchouc, or India-rubber, and gutta-percha are inspissated 
juices of certain tropical trees. Caoutchouc is elastic; gutta- 
percha is not. Both are hardened (vulcanized) by combining 
with sulphur. They are unaffected by most chemicals and sol- 
vents. Chloroform is their best solvent. 

The Alcohol Radicals, a homologous series of univalent 
basylous radicals, so called because they are the bases of the most 
important alcohols. Their compounds are numerous, and enter 
largely into the materia medica. In the following table a few of 
these compounds are given: j 



ORGANIC CHEMISTRY. 93 











Examples of Com- 










hols. 


Ethers. 


pound Ethers. 


Aide- 
hvde^ 


















Nitrates. Sulphates. 






Methvl, 


CH 3 


CH3HO 


'H: 20 


CH3NO1 fCH^ 2 S0 4 


CHaO 


CH2O2 


Ethvl, 


C2H5 


C2H5HO 


C2H5130 


C2HCNO3 [C2H5 2SO4 


C2H4O 


C2H4O2 


Propyl. 




C3H7HO 


< ;H- 2O 


C5H7NC = C 5H7 2SO4 


C3H6O 


• "--H-02 


Butyl. 


C*Hg 






C4H9N 2SO4 


G4H8O 


.'£ ~. 


Amvl. 


C5H11 


C5HIIHO 


c jHn : : 


C5H11NO3 CsHn 2SO4 


C5H10O 


C^HioOa 


HrXV;, 


C5H13 


C6HI3HO 


CfeHia 20 


C6H13NO3 C6H13 aSC - 




C-H12O2 


. etc 






etc. 


etc. 




etc. 



In the formation of these compounds the starting point is not 

the radicals, but their hydrates, the alcohols. When an alcohol is 

oxidized with a limited supply of oxygen, two atoms of hydrogen 

are removed and no oxygen is added. This forms the aldehyde, 

thus: 

Metkyl thyl 

alcohol. aldehyde. 

CH 3 HO-0=CHX>-H 2 0. 

If there is a full oxidation, an atom of oxygen takes the place of 

the two atoms of hydrogen removed and forms the corresponding 

acid, as : 

Methyl Formic 

alcohol. acid. 

CH t H0-0,=CH ; r -H 2 0. 
In the formation of aldehydes and acids the radical supplies 
part of the hydrogen removed and loses its identity. As part of 
the hydrogen in an acid forms the positive radical, it is written 
first: e. g. formic acid is written HCHCX, instead of CH.O-- The 
various other compounds of these radicals are called ethers; the 
oxides being called simple ethers, the others compound ethers. They 
are generally formed by treating the appropriate alcohol with the 
appropriate acid. 

Alcohols. The modern chemist accepts as alcohols many sub- 
stances that bear little resemblance to ordinary alcohol. 

Methylic Alcohol— CH 3 HO— Wood Xaphtha, Wood Spirit, 
Wood Alcohol, PyroUgncom Spirit. Methyl Hydrate — does not exist 
in nature. Made by the destructive distillation of wood. The 
commercial article has a very disagreeable odor and taste from 
the presence of tarry matters, etc. : but when pure methylic 
alcohol resembles ordinary alcohol in its properties and physio- 
logical action. It is not used in medicine, but is extensively 



94 ORGANIC CHEMISTRY. 

employed in the arts as a solvent, as in the preparation of 
varnishes, etc. 

Methylated spirit is ordinary alcohol to which has been added 
one tenth part of commercial methylic alcohol to render it unfit 
for drinking, and thus relieve it of the heavy tax imposed upon 
alcoholic beverages. 

Ethylic Alcohol— CJiflO— Ethyl Hydrate, Spirits of Wine, 
Vinic Alcohol, Alcohol. Alcohol does not exist in nature, but is 
produced in a number of reactions. Liquids containing it (wines, 
etc.) have been known from the remotest antiquity, and are ob- 
tained by allowing liquids containing glucose (grape sugar) to 
ferment. C 6 H I2 6 =2C 2 H 5 HO + 2C0 2 . 

Glucose. Alcohol. Carbon dioxide. 

The alcohol is then separated by distillation, for, being more 
volatile than the water, it passes over first. 

Commercial alcohol always contains water, and when pure or 
absolute alcohol is required, the commercial article is mixed with 
some substance which is very avid of water, as quicklime, and 
then again distilled. 

Alcohol is a light, colorless liquid, of a pleasant, pungent odor 
and burning taste. Has a great affinity for water, which prob- 
ably accounts for its preserving animal tissues and coagulating 
albumen. 

It is largely used in the arts and in pharmacy, principally as 
a solvent; but also in the manufacture of various substances, as 
vinegar, chloral, chloroform, iodoform,* ether, etc.; and as a fuel 
when a hot and smokeless flame is needed ; and as a menstruum 
in the preparation of tinctures and spirits. 

Alcoholic solutions of fixed medicinal substances are called 
tinctures; those of volatile principles, spirits. 

Alcohol is employed in various forms and degrees of concen- 
tration. Absolute alcohol is rarely employed. Alcohol fortius, U. 
S. P., stronger alcohol, contains 92 per cent of alcohol. Alcohol, 
U. S. P., is the ordinary rectified spirit, and contains 85 per cent 
of alcohol. Alcohol dilutum, U. S. P., diluted alcohol, is made by 
mixing water and alcohol, equal parts. 

* Experiment. To test for alcohol in a solution: Warm; add a few scales 
of iodine, and then caustic potash until the color is discharged. On cooling 
yellow scales of iodoform are deposited. 



ORGANIC CHEMISTRY. 95 

Spiritus frumenti, U. S. P., whisky, and spiritus vini gallici, U. 
S. P., brandy, are obtained by distillation; the former from fer- 
mented grain, and the latter from fermented grape juice. They 
contain about 50 per cent of alcohol. They are colored by the 
addition of caramel (burnt sugar). Their flavor is due to small 
quantities of other alcohols produced in the fermentation, and 
to certain ethers formed from these alcohols, especially as the 
liquor "ages." 

A large class of alcoholic beverages are made by fermenting 
various liquids containing sugar or some substance capable of 
conversion into sugar. 

Beer, ale, and porter are infusions of malted grain, fermented 
and flavored with hops. They therefore contain the soluble con- 
stituents of the grain. Their alcoholic strength is about 5 per 
cent. Wines are prepared by allowing grape juice to ferment. 
The alcoholic strength of the different varieties varies from 10 to 
25 per cent. Sherry (vinum Xericum) and port (vinum rubrum) are 
the only ones officinal. Cider is the fermented juice of the apple, 
prepared very much in the same way as wine is from grape juice, 
and contains about 5 per cent of alcohol. It is very prone to 
acetous fermentation and liable to produce colic and diarrhea. 

Alcohol, when concentrated, abstracts water from the tissues 
and coagulates their albuminoid constituents, and is a poison. 
In full doses (always best with food) it produces a sense of warmth 
in the stomach, general comfort and exhilaration, followed by 
incoherence of ideas and impairment of muscular co-ordination. 
Taken habitually, in any of its forms, it impairs the mental and 
moral force of its victim and produces in the various organs, 
especially the liver and kidneys, the degenerative changes char- 
acteristic of chronic alcoholism. It should never be taken in 
health, but as a medicine it is the most valuable of stimulants. 
In cases of acute poisoning by alcohol, the stomach and bladder 
should be evacuated, and the depression (coma) counteracted by 
strong coffee, the cold douche, and other stimulants. 

Amylic Alcohol— C 5 H It HO— Amyl Hydrate, Fusel Oil. This 
is a heavy liquid, soluble in alcohol but not in water, hence in- 
correctly called an oil. It is produced in the fermentation of 
grain and potatoes, and is the most deleterious impurity in com- 
mon whisky before it has undergone the refining process. 



96 ORGANIC CHEMISTRY. 

It has a penetrating, disagreeable odor, resembling that of 
mean whisky. Although not fragrant itself, its ethers, when dis- 
solved in ethylic alcohol, have the taste and odor of various fruits, 
and are used in the preparations of artificial fruit essences.* 

The other alcohols of this series are of no medical interest. 

Glycerylic Alcohol— C 3 K s 3'H.O— Glyceryl Hydrate, Glycer- 
ine. This is a sweet, viscid liquid, formed incidentally in the 
preparation of lead plaster, and in the manufacture of soap and 
candles. It is colorless and odorless, and neutral in reaction ; a 
solvent of a great many mineral and organic substances. It dis- 
solves freshly precipitated tannate of quinine (five grains to the 
ounce), and the solution is scarcely bitter. When glycerine is 
treated with strong nitric acid nitro-glycerine, C 3 H 5 3N0 3 results, 
one of the most dangerous of explosives. Dynamite is a mixture 
of nitro-glycerine and sand. Glycerine is used in medicine mainly 
as a solvent and as a local application. 

Mannityl Alcohol — C 6 H 8 6HO — Mannite. This is the prin- 
cipal ingredient in manna, a white, gummy substance exuding 
from certain trees. Mannite is a crystalline substance closely 
resembling glucose, except that it does not undergo the vinous 
fermentation, and does not respond to Trommer's or Fehling's 
tests. 

Ethers. The simple ethers (oxides) are the results of dehy- 
drating two molecules of alcohol by means of sulphuric acid; the 
compound ethers are made by treating the appropriate alcohol with 
the appropriate acid. 

Ethyl Oxide — (C 2 H 5 ) 2 — Sulphuric Ether, Ether. Ether is 
made by distilling a mixture of alcohol and sulphuric acid;f 
hence the misnomer, sulphuric ether. 

A small quantity of sulphuric acid is capable of converting a 
large amount of alcohol into ether, for it is unaltered in the re- 
action ; in fact, the process might go on indefinitely but for the 

* Experiment. To a half dram of fusel oil in a test-tube add some sodium 
or potassium acetate and a few drops of sulphuric acid. Warm the mixture, 
and the acetate of amyl (essence of pear) may be recognized by its odor. 

t Experiment. Into a large test-tube pour alcohol and half as much sul- 
phuric acid ; warm and note the odor of the ether evolved. Next adapt a cork 
with delivery tube, and slowly distill the ether into a cool test-tube. By adding 
more alcohol the operation may be repeated again and again. 



ORGANIC CHEMISTRY. 97 

acid being so diluted with the water derived from the alcohol, as 
to finally stop the reaction. The sulphuric acid is said to act by 
its mere presence, by catalysis; or, in other words, it acts because 
it acts, a ready but feminine way of explaining many otherwise 
inexplicable chemical and physiological phenomena. 
The true rationale is as follows: 

C 2 H 5 HO+H 2 S0 4 =C 2 H 5 HS0 4 +H 2 0, 
And then 

C 2 H 5 HS0 4 +C 2 H 5 H0=(C 2 H 5 ) 2 0+H 2 S0 4 . 

Ether is a colorless, very volatile liquid of a peculiar odor, 
called ethereal. It burns easily, and its vapor, mixed with air or 
oxygen, explodes when ignited ; * so ether should never be used 
near, especially above, a flame. Ether is a valuable solvent, and, 
as it evaporates very rapidly, it is used to produce cold.f But its 
chief use in medicine is an anaesthetic. Being less liable to para- 
lyze the nerve centers, it is safer than chloroform. 

Ethyl Chloride — C 2 H_C1. Hydrochloric ether must not be 
confounded with the so-called chloric ether, which is an alcoholic 
solution of chloroform. 

Ethyl Bromide — C 2 H 5 Br — Hydrobromic Ether. A valuable 
anaesthetic, but not much used. 

Ethyl Nitrite — C 2 H 5 N0 2 — Nitrous Ether. If nitric acid be 
treated with copper or starch it loses part of its oxygen, being 
converted into nitrous acid (HN0 2 ), which will unite with alco- 
hol, forming nitrous ether and water, thus: 

C 2 H 5 H0+HN0=C 2 H 5 N0 2 +H 2 0. 

Nitrous ether is a yellowish liquid, of an apple-like odor and 
sweetish taste. It is used only diluted with alcohol, forming the 
spiritus cetheris nitrosi, U. S. P., commonly called sweet spirits of niter. 

Amyl Nitrite— C 5 H ri N0 2 . Made like ethyl nitrite, except 
that amylic alcohol is used. Nitrite of amyl is a volatile, oily 
liquid, of a peculiar odor, resembling that of bananas. It is 
given by inhalation, especially in epilepsy, for which purpose it 
is put up in glass bulbs holding about two drops. These are 
crushed and inhaled during the aura. 

* Experiment. Put a dram of ether in a dish and apply a flame. The 
vapor, mixed with air, explodes ; the rest burns rapidly. 

t Experiment. Set a test-tube of water in a beaker of ether. Blow air 
briskly through the ether ; the water will freeze. 



98 ORGANIC CHEMISTRY. 

Chloroform — Trichlormethane. Methyl, having only one free 
valence, must give up two atoms of its hydrogen in order to com- 
bine with three atoms of chlorine, making the formula of chlo- 
roform CHC1 3 . This is the most used of all the ethers. Chlo- 
roform is made by distilling a mixture of chlorinated lime, 
water, and ordinary alcohol. It is a colorless, volatile liquid, 
of a pleasant ethereal odor and sweet taste. It is heavier than 
water, and does not dissolve in it, but is soluble in alcohol and 
ether; not easily ignited; a good solvent for phosphorus, iodine, 
India-rubber, and the alkaloids. Chloroform is sometimes given 
by the stomach as a sedative, but most frequently administered 
by inhalation as an anaesthetic, for which purpose it should be of 
undoubted purity. Pure chloroform is not colored by an equal 
volume of pure sulphuric acid, nor should its specific gravity be 
below 1480. 

Toxicology. If chloroform be taken by the stomach, it being 
insoluble, is absorbed very slowly; and its principal action is the 
local irritation of the mucous surfaces. Eecovery has followed a 
dose of four ounces, and death has been caused by one dram taken 
into the stomach. The vapor acts more energetically, and seems 
to owe its potency for evil to its paralyzing influence on the nerve 
centers, especially those of the heart. So chloroform vapor should 
never be administered except by a capable physician, and well 
diluted with atmosphere. However, death has occurred from the 
inhalation of moderate quantities of chloroform properly diluted, 
and at the hands of careful physicians, and the autopsy revealed 
no heart lesion. 

There is no chemical antidote for chloroform. When it has 
been swallowed, evacuate the stomach ; when inhaled, lower the 
head, give fresh air, employ artificial respiration, and apply the 
induced current. 

The poison is usually recognized by its odor. 

Iodoform — CHI 3 — Made by the action of iodine and potash on 
alcohol ; yellow scales ; insoluble in water, and of a saffron-like odor, 
which is the chief objection to its use. Light decomposes it, giv- 
ing it a violet color. Iodoform is used on ulcers, etc., as an anaes- 
thetic, alterative, and antiseptic. 

Fixed Oils and Fats. These are ethers — combinations of 
glyceryl (C 3 H S ) with the fat acids, oleic, stearic, butyric, palmitic, 



ORGANIC CHEMISTRY. 99 

etc. The natural fata are mixtures of these. Those contain- 
ing mostly oleate of glyceryl (olein 1 * are liquid. Warm-blooded 
animals yield mostly solid, cold-blooded, liquid fats. Drying oils 
are such as absorb oxygen from the air and become resinous, t 
linseed. Many fats partially decompose on exposure, producing 
free acid, and become rancid. The fixed oils are insoluble in 
water, soluble in alcohol, ether, and chloroform. 

The compounds of the fatty acids with metallic radicals are 
called soaps. Soaps are made t f a fat with a 

caustic alkali. Fur example: 

rine. Sodium stearate. Glvcerine. 

H f t " : :H :5 a )3-3XaHO=3XaC l3 H 3S 0,+C 3 E s (HOX 
All the soaps are insoluble, except those of the alkali metals (K, 
Na, NH 41 etc.). This explains the curd, soap precipitates in hard 
water-. Lead soap (lead is officinal. When soap dis- 

solves in cold water, it decomposes into an acid salt which makes 
the soapsuds and a small quantity of free alkali which does the 
cleaning. 

Aldehydes. An unimportant class. They constitute the first 
step in the oxidation of alcohols into i he removal of 

hydrogen (hence the name;. Since nothing has taken the place 
of the hydrogen removed, they are unsaturated and very prone to 
change, especially to take on oxygen and form the acids. 

Ethyl Aldehyde, acetic aid: - i ruply aldt : : \ d* ~ C -H.O), 

is a colorless, volatile, acid liquid of a pungent odor. One of its 
modifications, called paraldehyde, is used as a hypnotic, which 
unlike morphine is followed by no unpleasant effects, except a 
pungent odor to the breath. Dose, 5^s-5j. 

Chloral. If chlorine displace three atoms of hydrogen in 
ethyl aldehyde, it forms tri-chlor-aldehyde or chloral CJBCLO . a 
colorless, heavy liquid. With a molecule of water this forms a 
white crystalline solid, called chloral hydrate, having a pungent 
but agreeable odor and taste. Warmed with an alkali it decom- 
poses, thus : 

Chloral. Sod. formate. Chloroform. 

C,RCl ; 0-XaHO-XaCHO, - CH( 

* Experiment. To a little bichromate and sulphuric acid mixture in a 
-tube add a little alcohol; or hold a hot glass rod in a beaker containing a 
little ether. The peculiar pungent odor is that of aldehyde. 



100 ORGANIC CHEMISTRY. 

Liebriech thought this reaction would occur in the warm alkaline 
blood and the sedative action of chloroform be obtained. Though 
mistaken in this, he found chloral hydrate a valuable hypnotic. 
The chloral habit is difficult to cure. In overdoses chloral is a 
poison, and cases are multiplying as its powers become better 
known. No chemical antidote. Evacuate the stomach, give stim- 
ulants, and maintain the respiration and bodily warmth. 

Organic Acids. These are regarded by chemists as the nat- 
ural results of the oxidation of alcohols. But as most of them 
were discovered before their relation to the alcohols were known, 
their names often have no connection with those of the alcohols. 
We take up only the most important. 

Acetic Acid — HC 2 H 3 2 . This is the acid of vinegar. Formed 
in a great many reactions, but made mainly by the destructive 
distillation of wood, or by the oxidation of ordinary alcohol. If 
wine, cider, or other alcoholic liquors be exposed to the air, a 
fungus (micoderma aceti) forms on the surface and acts as an 
oxygen carrier, and the alcohol is converted into acetic acid, 

thus: C 2 H 5 H0+0 2 =HC 2 H 3 2 +H 2 0. 

A more rapid process is to pass the alcohol through -barrels 
filled with beech shavings. 

Acetic acid is a colorless liquid, of a pungent, sour taste and 
smell. When free from water (glacial) it crystallizes at temper- 
atures below 60° F. Acetic acid in dilute solution (vinegar) is 
much used for domestic purposes. For medicinal use the crude 
vinegar is purified by distillation, forming acidum aceticum di- 
lutum, U. S. P. 

As all the acetates are soluble, their best test is to add a strong 
acid and recognize the acetic acid set free by its odor. 

Benzoic Acid exists in many balsams and gum-resins. When 
benzoin is heated benzoic acid sublimes in silky needles of a pleas- 
ant balsamic odor. Or, if the urine of herbivorous animals be 
boiled with hydrochloric acid, the hippuric acid is converted into 
benzoic acid. But the acid obtained from this source may be 
known by its urinous odor. 

Carbazotic or Picric Acid is a yellow substance, of a bitter 
taste, made by the action of nitric acid on carbolic acid. Used in 
the arts as a yellow dye. 



ORGANIC CHEMISTRY. 101 

Carbolic Acid — C 6 H 5 HO — Phenyl Alcohol, Phenol This is 
an alcohol, the hydrate of phenyl, a radical of the aromatic series. 
Called an acid 'because it combines with bases and forms bodies 
resembling salts called carbolates or phenates. 

Carbolic acid is formed in a number of reactions, but the com- 
mercial article is obtained exclusively from coal tar. It has a 
strong, disagreeable odor; occurs as white crystals, which melt 
on the addition of a small quantity of water ; reddens by age ; 
slightly soluble in water, but very soluble in glycerine, the solu- 
tion being soluble in water; stains skin and mucous membranes 
white by coagulating their albumen; and is a corrosive poison. 
Albumen is its best antidote. 

Carbolic acid is a powerful antiseptic and disinfectant. Ap- 
plied locally it is astringent, sedative, and even anaesthetic. 

Resorcin — (C 6 H 4 2HO). Closely related to phenol, but a stronger 
antiseptic and much less poisonous. It occurs in soluble, color- 
less, odorless crystals of a sweetish taste. It is given as an anti- 
zymotic in diseases attended with fermentative changes and in 
the* specific fevers. 

Creasote is a complex mixture obtained from wood tar ; closely 
allied to carbolic acid in its properties and uses, but may be read- 
ily distinguished from it by being insoluble in glycerine. 

Citric Acid exists in the juices of many fruits, especially the 
lemon. Forms colorless crystals which are very soluble, and pos- 
sess a sour taste. Many of its salts are used in medicine. 

Formic Acid— HCH0 2 — is the oxidation product of methylic 
alcohol. It was formerly obtained from the red ant {formica 
rufa), but now made artificially. It exists in stinging nettle, 
pine needles, etc., and also in the stings of most insects. 

Gallic Acid. When galls are moistened and exposed to the 
action of the atmosphere, the tannic acid they contain is con- 
verted into gallic acid. It resembles tannic acid, but may be 
distinguished by its not precipitating a solution of gelatin. 

Lactic Acid (lactis, of milk). This is the acid of sour milk, 
where it is formed by the fermentation of the sugar of milk 
through the agency of the casein. It is also formed^in the body 
by the decomposition of glucose, thus : 

C 6 H I2 6 -2H 2 C 3 H 4 3 . 
It is a syrupy liquid, of a very sour taste. 

H 



102 ORGANIC CHEMISTRY. 

Malic Acid {malum, an apple) exists in many fruits, as ap- 
ples, cherries, etc., and very abundantly in garden rhubarb. 

Oxalic Acid— H 2 2 4 . The acid and its salts are found in 
many plants, especially the sorrel (oxalis) grasses. In certain 
pathological conditions it is formed in the body and eliminated 
in the urine as calcium oxalate. It is made in large quantities 
by the action of nitric acid on sugar, or of alkalies on saw-dust. 
Oxalic acid closely resembles Epsom salts, for which it is some- 
times taken by mistake. It is a powerful irritant poison. Being 
cheap and largely used for removing ink stains, cleaning copper, 
etc., poisoning by oxalic acid is by no means rare. Its best anti- 
dote is chalk, or some other compound of calcium, with which it 
forms a very insoluble compound. 

Test. Calcium chloride gives a white precipitate, insoluble in 
acetic, but soluble in hydrochloric acid. 

Pyrogallic Acid sublimes as. white, feathery crystals when 
gallic acid is heated. Used in gas analysis to absorb oxygen, as 
a^deoxidizer in photography, and as a hair dye. 

Test. A blue color with ferrous, and a red with ferric salts. 

Salicylic Acid. Formerly prepared from salicin, but now 
made by a patented process from carbolic acid. A very pure acid 
may be obtained from oil of wintergreen, which consists mainly 
of methyl salicylate. This, treated with potassium hydrate, forms 
methyl hydrate (methyl alcohol) and potassium salicylate; and 
if to this hydrochloric acid be added, potassium chloride will be 
formed, and salicylic acid will fall in a mass of silky, white 
crystals. Salicylic acid is scarcely soluble in cold water, hence 
the^ salicylate of sodium is usually prescribed, which is not only 
more soluble, but less irritating to mucous membranes. 

Test. Intense violet with a ferric salt. 

Succinic Acid was first obtained from amber (succinum), but 
is now made by fermenting malic acid. 

Tannic Acid, or Tannin. This is the active principle of the 
vegetable astringents; usually obtained from oak galls; a green- 
ish or brownish powder, very soluble in water, of a rough, as- 
tringent taste. It precipitates solutions of salts of the alkaloids 
and most metals. It precipitates gelatin and other albuminoid 
substances, a fact that explains the process of tanning raw hides. 
With ferricjsolutions tannin gives a black precipitate (black ink). 



ORGANIC CHEMISTRY. 103 

Tartaric Acid— H 2 C 4 H 4 6 , or H 2 T. Tartrates exist in the 
juices of many fruits. Grape juice contains much acid tartrate 
of potassium (KELT), which, being very insoluble in an alcoholic 
menstruum, is precipitated on the sides of the cask whenever the 
wine ferments. This forms argol, the principal source of tartaric 
acid. Tartaric acid forms colorless crystals, very soluble, and of 
a sharp, agreeable, sour taste. 

Valerianic Acid — HC 5 H 9 2 . This substance was first ob- 
tained from valerian root; but now it is made artificially by 
oxidizing amylic alcohol by means of sulphuric acid and po- 
tassium bichromate. Valerianic acid is a colorless liquid, pos- 
sessing the disagreeable odor of valerian. 

The Carbohydrates. These substances are closely related to 
the alcohols, and by some classed as such. They are so named 
because they contain carbon (six or twelve atoms), and the hy- 
drogen and oxygen they contain are in the exact proportion to 
form water. They constitute the bulk of plants. They are di- 
vided into three groups: 

1. Amyloses (C 6 H io O s ), which include cellulin, starch, dex- 
trin, glycogen, gums, etc. 

2. Saccharoses (C I2 H 22 xi ), including cane sugar, milk su- 
gar, etc. 

3. Glucoses (C 6 H I2 6 ), such as grape sugar (glucose), fruit 
sugar, etc. 

Although the members of each of these groups differ widely 
in their physical and chemical properties, still they consist of the 
same elements in exactly the same proportions and have the same 
formula. Such bodies are said to be isomeric. 

AMYLOSES— (C 6 H I0 5 ). Cellulin— Cellulose, Lignin— forms 
the cell-walls and tissues of plants. Woody fiber, cotton, linen, 
and unsized paper are almost pure cellulin. Dissolves only in a 
solution of cupric oxide in ammonia. Acids precipitate it as a 
white mass, which, mixed with camphor and compressed, is cellu- 
loid. Unsized paper dipped into moderately strong sulphuric 
acid, washed and dried, has its fibers agglutinated, loses its poros- 
ity, becomes very tough, and is sold as artificial parchment for 
dialyzers, diplomas, etc. 

Nitro-cellulose, or Gun Cotton, a powerful explosive, is cotton 



104 



ORGANIC CHEMISTRY. 



that has been dipped into a mixture of nitric and sulphuric acids, 
and then washed and dried. Its solution in ether is collodion. 
The flexible collodion contains a little turpentine and castor oil ; 
the styptic collodion contains twenty per cent tannin. 

Starch — Arnylum — the most important member of the carbo- 
hydrates, and a valuable food; found in the roots, stems, and 

seeds of all plants. Starch 
is a white powder, consisting 
of granules, formed of con- 
centric layers, like an onion. 
These granules have all a sim- 
ilar appearance. Yet those 
from different kinds of plants 
differ enough to enable one, 
by microscopic examination, 
to determine the source of 
any starch. (Fig. 64.) 

When starch is boiled the 
granules swell and burst, cast- 
ing the starch into the water, 
forming mucilage of starch, which is used for laundrying and 
for surgical dressings. Starch is a very valuable food. The best 
test for starch is iodine, with which it forms a blue. Heat dis- 
charges the blue, but it returns on cooling. 

Dextrin — British Gum — is the gum used on postage stamps, 
etc. It may be made from starch in various ways, one of which 
is by heating it to 300° F. It is very soluble, and gives no blue 
with iodine. 

Glycogen — {Generator of Glucose) — is found in the animal 
economy, especially in the liver. Like dextrin, it is a derivative 
of starch, but differs from it in being soluble, and giving only 
a wine-color with iodine. It seems to be the form in which the 
carbohydrates are stored up, to be used by the system as neces- 
sity arises. 

Gums are a class of substances soluble in water, but insoluble 
in alcohol. A type of the class is gum Arabic. 




Fig. 64. 



(a) potato, (b) corn, (c) bean 
starch. 



SACCHAROSES — CJ^A,. Cane Sugar— Beet Sugar, Su- 
crose. Very abundant in the sugar-cane, sugar-maple, beet-root, 



ORGANIC CHEMISTRY. 105 

etc. It is the most soluble, perfectly crystallizable, and sweetest 
of the sugars, and the one most used for domestic purposes. Its 
aqueous solution is called simple syrup (syrupus simplex). 

Milk Sugar, as its name implies, occurs in milk ; harder, less 
soluble, and less sweet than cane-sugar. Used in the trituration 
of medicines. 

GLUCOSES — C 6 H I2 6 . Glucose— Grape Sugar, Diabetic Su- 
gar. Found associated with other sugars in most plants, especially 
in the grape ; but the source of 
most interest to the physician is 
the animal economy. This is the 
sugar of diabetic urine, and the 
ability to detect it with ease and 
certainty in such conditions is a 
necessity to the practitioner of the 
present day. 

Glucose is not so sweet nor so 
soluble and crystallizable as cane- 
sugar. Having great affinity for 
oxygen it is a valuable reducing 
agent, and on this property most Flg * 65 - 

of its tests depend. Boiled with a dilute mineral acid or allowed 
to remain under the influence of certain animal and vegetable 
ferments,* warm and moist, the amyloses and saccharoses are 

"•Ferments. These are certain nitrogenous bodies, animal and vegetable, 
which by some means not clearly understood cause many organic compounds 
to decompose with the production of other and simpler substances, the ferments 
themselves being unaffected. Ferments are of two classes : 

1. The unorganized, or soluble ferments. Among these are: (a) Diastase, or 
maltin, formed from the gluten and serving to convert the starch of the seed 
into glucose. Malt, which is sprouted barley, contains it in abundance, and is 
used to convert meal (starch) into glucose for fermentation in the manufacture 
of alcoholic liquors, and in medicine as a digestive agent. The ptyalin of saliva 
and a pancreatic ferment act like diastase, (b) Pepsin, of the gastric juice, and 
(c) Trypsin, of the pancreatic fluid, both of which serve to convert the albumi- 
noids into peptones; the one in acid, and the other in alkaline solution. 

2. Organized Ferments. "When their spores are carried by the atmosphere or 
otherwise into a suitable, fermentable liquid, and kept warm (68° to 105° F.), 
these ferments grow and proliferate with great rapidity, inducing fermentative 
changes in a few hours. The most important of these ferments are: (a) Yeast 
(torula cerevisise), shown in Fig. 65. This converts glucose into alcohol and car- 
bon dioxide (vinous fermentation), {b) Acetic acid ferment (mycoderma aceti), 




106 ORGANIC CHEMISTRY. 

converted into glucose. The reaction consists in the addition 
of H 2 to the molecule, thus : 

C 6 H IO 5 +H 2 0=C 6 H I2 6 . C I2 H 22 II +H 2 0=2C 6 H I2 6 - 

Starch. Water. Glucose. Cane Sugar. Water. Glucose. 

When starch and cane-sugar are eaten the digestive ferments 
(pancreatin and ptyalin) convert them into glucose. The fer- 
ment (diastase), developed in a germinating seed, converts the 
starch into glucose, which is readily assimilated by the sprout- 
ing plant. 

Glucose is so easily made by boiling cellulin, but more es- 
pecially starches, with sulphuric acid, that it has become a com- 
mon adulterant or substitute for cane sugar, especially syrup. 
This would be harmless but for the fact that the cheap acid used 
is apt to be contaminated with lead, arsenic, etc. 

Grlucosides. This class includes a large number of bodies, 
mostly of vegetable origin, which, though different in other re- 
spects, possess one common property, viz: When acted upon by 
a ferment or a dilute acid they decompose, producing, among 
other things, glucose. Their chemical constitution is not defi- 
nitely known, but probably they are ethers of glucose. In the 
natural state they are generally associated with an albuminoid 
body capable of acting as a ferment, and gradually decomposing 
them with the production of glucose. This explains why some 
fruits (e. g. a persimmon) on ripening lose their rough, astringent 
taste and become sweet. The tannin {tannic acid) is converted 
into glucose. It also explains why a mustard poultice made with 
hot water is inert. The ferment is coagulated and the glucoside 
(myronic acid) does not decompose. 

The glucosides of greatest medical importance are : Amygdalin 
(bitter almonds), cathartic acid (senna), colocynthin, digitalin, 

commonly called " mother of vinegar," grows on solutions containing alcohol, 
which it helps to oxidize into acetic acid, (c) Thrush fungus {oidium albicans) 
grows within the mouths of ill-kept children. It induces a slight alcoholic fer- 
mentation, (d) Lactic and Butyric ferments go together, the one preceding and 
the other closely following. These fermentations occur in intestinal indiges- 
tion, and the gas evolved produces flatulent colic. 

Putrefaction (the spontaneous decomposition of nitrogenous organized 
bodies) is accompanied, if not caused, by micro-organisms, usually bacteria. 
Decay, on the other hand, is the gradual decomposition of organic bodies by 
the slow action of oxygen, and does not depend on living organisms. 



ORGANIC CHEMISTRY. 107 

elaterin, glycerrhizin (licorice), indican (source of indigo-blue), 
jalapin, rnyronic acid (mustard), santonin, tannin, etc. Their 
names terminate with the syllable "-in." 

Nitrogenous Bodies. Many of these (the proteids, etc.), are 
described in physiology, and need not be treated here. 

Bodies of the Ammonia Type. Taking the molecule of 
ammonia, NH 3 , as a basis, and by substituting for one or more 
atoms of its hydrogen one or more organic radicals or combina- 
tions of radicals, we can obtain a large number of interesting and 
important substances, known as amines, etc. For example : 



f H 


( C *H 3 


(C 6 H. 


(CH 3 fC 6 H 3 


N^H; 


N^H = ; 


N H = ; 


N^CEL; N^H 


(h 


(h 


(H 


1. CH 3 ( C 2 H 3 2 


Ammonia. 


Ethylamine. 


Phenylamine. 


Trimethylamine. Acetanilide, 



Like ammonia, these bodies are alkaline and combine with acids 
to form salts, appropriating instead of displacing their hydrogen, 
e. g. NH 3 +HC1 = NH 4 C1, ammonium chloride or ammonia hy- 
drochloride; in like manner NH 2 (C 2 H 5 )+HC1-NH 2 (C 2 H 5 )HC1, 
ethylamine hydrochloride. There is perhaps no other field in 
chemistry so promising to the discoverer of therapeutic agents. 
Numerous and important as these substances are, we can men- 
tion only a few. 

Aniline (Phenylamine) is a colorless liquid, but its coin- 

( C6H. pounds (the aniline dyes) are coloring matters of great 
Nj H D brilliancy.* They are sometimes contaminated with 

I -°- arsenic used in their manufacture. 

Trimethylamine is sometimes confounded with propylamine. 

' CH It i s a colorless, volatile alkaloid, with an ammoniacal, 
CH 3 fishy odor. It is found in many animal and vegetable 

( CH 3 substances, but obtained from pickled herring. The 
hydrochloride is the salt used. Dose, ten to fifteen grains. 

Antifebrin (acetanilide). This is a derivative of aniline in 

( C H which the acetic radical is made to displace an atom 
N \ H of hydrogen. A crystalline, odorless, solid, slightly 

( C 2 H 3 2 so i u ]3] e [ n warm water, very soluble in alcohol. In 

* Experiment. Dissolve a few drops of aniline in water in two test-tnbes. 
To one add solution of chlorinated lime— a purple color is produced; to the 
other add some sulphuric acid and potassium chromate mixture — a blue color 
appears. 






108 ORGANIC CHEMISTRY. 

doses of five to ten grains, repeated every two or three hours, it is 
an antipyretic and sedative. It is said not to affect the healthy 
temperature, but to rapidly lower a fever. 

Antipyrine, a derivative of the artificial alkaloid, chinoline, 
is a white crystalline powder, soluble in water and alcohol, of a 
slight tarry taste and odor. The hydrochloride is the salt used. 
In doses of ten to fifteen grains it is a valuable antipyretic and 
anodyne. 

Urea belongs to this class, but is described further on in con- 
nection with the urine. 

Alkaloids (alkali-like). These bodies are mostly of vegetable 
origin and bear a close analogy to the preceding, for they are 
ammonia substitution compounds, alkaline in reaction, and com- 
bine with acids to form salts. Of late years chemists have made 
substances very similar to, if not identical with, some of the nat- 
ural alkaloids ; and the time seems not far distant when our most 
costly alkaloids will be made cheaply by artificial means. In 
plants alkaloids are not found free, but combined with some veg- 
etable acid forming a salt. Their salts (except tannates) are usu- 
ally soluble and intensely bitter; the free alkaloids being much 
less soluble, are much less bitter. Those alkaloids (as conine and 
nicotine) that contain no oxygen are liquid; but the great ma- 
jority of them are white powders. 

Alkaloids are so seldom prescribed in the free state that when 
the simple name of an alkaloid is written in a prescription the 
druggist puts up its most common salt. The names of alkaloids 
end in u -ine," and are derived from the names of the plants in 
which they exist or from some characteristic property. 

The intense effect alkaloids exert on the animal organism 
makes them generally the active principles of the drugs in 
which they are found. * But the active principle of a drug is 

* Proximate and Ultimate Principles. Most organic bodies in their nat- 
ural state are mixtures of several different substances ; e. g. common resin is a 
mixture of two or three hydrocarbons, butter of four or five fats, opium and 
cinchona of several dozen compounds, while brain matter is of such com- 
plex composition that no satisfactory analysis has ever been made. These 
substances that naturally exist, mixed together to form a body, are called its 
proximate principles. The separation of these unaltered from the body and 
from each other is called proximate analysis. In this, different methods must 
be devised for different substances. For example: Take a piece of vegetable 



ORGANIC CHEMISTRY. 109 

not always an alkaloid. The alkaloids include the majority of 
our most potent remedies and powerful poisons. Tannin is a 
common antidote, but most important is the prompt evacuation 
of the stomach and the intelligent use of physiological antago- 
nists. 

The alkaloids, even those of medical interest, are so numerous 
that to give each separate consideration would cover a great por- 
tion of the materia medica. We can mention but a few of the 
most important. 

Opium Alkaloids — Morphine {Morpheus, the God of Sleep), 
Codeine, Narcotine, etc. — exist in the plant combined with me- 
conic acid. The red color this acid gives with Fe 2 Cl 6 is the best 
test for opium. Morphine gives a dirty blue with Fe 2 Cl 6 . Apo- 
morphine is made by heating morphine and hydrochloric acid to 
300° F. It is an emetic. 

Cinchona Alkaloids — Quinine, Quinidine, Quinoidine, Quini- 
cine, Cinchonine, Cinchonidine, Cinchonicine, etc. The sulphate and 
bisulphate are the salts generally used. 

Test for Quinine. Add chlorine water, shake, and then add 
aq. ammonise ; a green coloration is produced. 

Nux Vomica Alkaloids — Strychnine and Brucine. Violent 
poisons. 

Tests. Strychnine dissolved in sulphuric acid and treated with 
potassium bichromate forms a purple. Brucine treated with nitric 
acid gives a deep red. 

tissue containing woody fiber, starch, sugar, resin, and volatile oil. The oil 
is removed by a gentle heat ; the resin is dissolved out by alcohol ; the sugar 
by cold water, and the starch by boiling in water, leaving the woody fiber. 

The Ultimate Principles of a body are the elements (carbon, hydrogen, etc.) 
of which it is composed, and the recognition and measuring of these is ultimate 
analysis. This, while requiring careful manipulation, is simple in principle. 
The body is burned with a full supply of oxygen, converting the carbon into 
CO2 and the hydrogen into H2O. These are collected and weighed, and the 
quantities of carbon and hydrogen in them are calculated. The amount of 
oxygen, if any, is determined by subtracting the sum of the carbon and hy- 
drogen from the weight of the original body. For example: 46 grains of 
alcohol (C, H and O) burned completely makes: 

88 grains of CO2 equivalent to 24 grains of C. 

54 grains of H2O equivalent to 6 grains of H. 

46 grains alcohol, minus 30 grains (24+6), = 16 grains of O. 
The less common elements, chlorine, nitrogen, sulphur, phosphorus, etc., 
are determined by special methods. 



110 ORGANIC CHEMISTRY. 

Liquid Alkaloids — Nicotine from tobacco, and Conine from 
hemlock — contain no oxygen. Virulent poisons. 

Cocaine, from coca leaves, is a valuable local anaesthetic; 
much used in minor surgery. The hydrochloride is the salt used. 

Ptomaines (7rr&)//a, a corpse). This name is given to certain 
alkaloids formed in animal and some vegetable bodies during 
putrefaction, and in some pathological conditions during Ufe. 
Their chemical properties and physiological actions are similar 
to those of the vegetable alkaloids. Some of them are extremely 
poisonous. The severe gastro-intestinal irritation and toxic 
symptoms often following the eating of spoiled meat are due 
to ptomaines. Recent investigators have succeeded in separat- 
ing from pyaemic fluids a definite alkaloid, and called it septicine. 
Our knowledge of the ptomaines is as yer very unsatisfactory. 



THE UKI2STE 




The urine is a fluid secreted continuously by the kidneys, and 
is the chief means by which the nitrogenous waste of the body is 
discharged. A specimen, to be representative, should be apportion 
of the whole twenty-four hours' urine, for con- 
siderable variation in composition and prop- 
erties may occur during the day. Especially 
is this true of traces of albumen and sugar. 
When this is impracticable, that passed before 
breakfast is generally preferable, because far- 
thest from a meal. When significant variations ^_ 
during the day are suspected, several specimens ^Hfe_ 
may be taken at different hours. For micro- 
scopical examination a few ounces of the urine Fi 66 
in a stoppered vial, or better still, in a cov- 
ered conical glass (Fig. 66) are set aside for several hours until 
the sediment has settled to the bottom and can be examined. 

Physical Properties. Normal urine is a transparent, aqueous 
fluid, of a pale yellow color, characteristic odor, acid reaction, and a 
specific gravity of 1020 when passed in the average quantity of about 
forty-five fluid ounces in the twenty-four hours. This description is 
to be taken with much allowance, for very wide variations occur 
even in health. With these variations the student must become 
thoroughly familiar before he is capable of interpreting a speci- 
men. Therefore the physical properties will be considered more 
particularly. 

Quantity. In health this depends upon (a) the amount of water 
ingested, and (b) its vicarious elimination by the skin, lungs, and 
bowels. Pathologically it is increased in diabetes, also in hys- 
terical conditions associated with convulsions and high arterial 
pressure, and after the administration of diuretics. 

Transparency. Normal urine is not always transparent, nor is 
transparent always normal. Some degree of opacity may be due 



112 



THE URINE. 



to: (a) Mucus, with some entangled epithelial cells,- which maybe 
observed in many specimens of healthy urine, especially of fe- 
males, because of the larger area of mucous surface in that sex. 
(b) Urates (of Na, K, Ca, and Mg), which often form a precipitate 
in urine, especially when allowed to stand over night in a cold 
room. The test for this sediment is heat, which quickly dissi- 
pates it. (c) Earthy phospates (of Ca and Mg), which may give 
an opacity to normal urine, especially if it is alkaline or even 
weakly acid. The test for this sediment is the addition of a few 
drops of any acid which promptly clears it up, while heat would 
only increase it. (d) Fungi (bacteria, penicillia, sarcinae, etc.), 
especially in decomposing urine. 

A urine may be abnormally opaque from the above causes, 
or from the presence of blood or pus. When due to blood or 
pus the opacity is increased by heat or acids because of the pre- 
cipitation of albumen always present in liquor sanguinis and 
liquor puris. 

Fluidity. Healthy urine is never otherwise than an aqueous 
fluid, flowing and dripping with ease; but in certain diseased con- 
ditions, abnormal quantities of mucus, or the presence of pus or 
fat, especially if the urine be allowed to decompose and become 
very alkaline, may give rise to viscidity. 

Color. Healthy variations in color depend mainly upon the 
amount of water and the consequent degree of concentration or 
dilution of the solid constituents. Aside from abnormal degrees 
of the above, pathological variations in color may be the result of 
(a) an increase or diminution of the normal coloring matters, as 
in fevers, etc. ; (b) the presence of abnormal substances, as biliary 
and blood coloring matters. Moreover, the urine may be colored 
after the administration of certain drugs, as senna, santonin, rhu- 
barb, prickly pear, etc. 

Odor. When freshly passed, urine has, in addition to its char- 
acteristic odor, an aromatic fragrance due to certain volatile 
ethers. Alkaline urine has an ammoniacal odor, unless the alka- 
linity be due to fixed alkali, when the smell is fainty and sicken- 
ing, like that of horses' urine. Diabetic urine exhales a sweetish 
smell. In certain forms of dyspepsia and liver trouble the odor 
of the urine is almost pathognomonic. Medicines and certain 
articles of food often impart a peculiar odor, as turpentine the 



THE URINE. 



113 



odor of violets, and asparagus and cauliflower a rank, disgusting 
smell. 

Reaction. Normally the urine of the whole twenty-four hours 
will average an acid reaction ; but great variations occur during 
the day. Before meals it will have a high degree of acidity, but 
after eating becomes nearly neutral, or even alkaline. This is 
due to the ingestion of food which is largely alkaline and to the 
abstraction of acidulous principles from the blood to form acid 
gastric juice. It has also been observed that urine passed on ris- 
ing in the morning is especially acid. This is probably due to the 
fact that during sleep less carbonic acid is exhaled from the lungs 
and less perspiration (acid) given off by the skin. The reaction 
of the urine is important to the physician, as it may favor or 
prevent the formation of sediments and concretions or irritation 
of the kidneys and bladder. The acidity of urine is due, not to 
free acid, but to acid sodium phosphate (JNaH 2 P0 4 ) occurring in 
consequence of carbon* 
ic, uric, and hippuric 
acids, seizing on to a 
portion of the sodium 
of the basic phosphate. 

An acid fermentation, 
attended with decom- 
position of mucus and 
coloring matters and a 
production of acetic 
and lactic acids, some- 
times occurs in urine 
that has stood for some 
time at a moderate tem- 
perature. After a while, 
more quickly in warm Fig. 67. Alkaline fermentation. 

weather, the alkaline fermentation begins, caused by the develop- 
ment of the micrococcus urese. (Pasteur.) The urea is converted 
into ammonium carbonate, thus : 

UH 4 N 2 0+2H 2 0=(NH 4 ) 2 C0 3 . 
This gives the urine an ammoniacal odor and alkaline reaction, 
and it becomes opaque from the precipitation of urate of ammo- 
nium and the earthy phosphates and the development of bacteria. 




114 



THE URINE. 



Pus and blood, or vessels tainted with urine previously fermented, 
greatly hasten this change. 

Specific Gravity. Though the average specific gravity is 1020, 
it exhibits, even in health, great variations, the extremes being 
1002 after copious use of water and diuretics, and 1040 after ab- 
stinence from fluid and the elimination of water through other 
means,-as profuse perspiration or copious diarrhea. The amount 
of solids varying but little in health, fluctuations in specific grav- 
ity are due mainly to variations in the amount of water, and, as 
long as the inverse proportion between specific gravity and volume 
of urine is preserved, variations need cause no alarm. 

Specific gravity is usually measured by an instrument called a 
hydrometer or urinometer (Fig. 68), which is a hollow glass float, 
weighted with mercury and having a long, gradu- 
ated neck. The graduation begins above at 1000, 
because the heavier the urine the less deeply will 
the instrument sink and the further the neck will 
protrude from the surface. It is well to test a 
new urinometer by immersing it in water at 60° F. 
(15.5° C), into which it should sink to or 1000 
on the scale. Urinometers are usually provided 
with a cylinder or jar, as shown in the figure, but 
a large test-tube will answer. This is about three 
fourths filled ; the urinometer is then introduced, 
and when still, the specific gravity is read off. 
Fig. 68. Thg C yii n( j er or test-tube should not be too nar- 
row, lest the urinometer be attracted to and 
catch against the sides, and not rise as high 
or sink as low as it should. The fluid being c '" 
attracted up around the stem, the reading 
should be made not along the line c d, as in 
the diagram, but a b, which represents the true 
level of the liquid. We may approximate the amount of solids 
in any urine by doubling the last two figures of the specific 
gravity, which will give the per cent. Thus, 'if a urine be of spe- 
cific gravity 1020, doubling the last two figures gives .040, or 4 
per cent. If the daily volume be fifty ounces, 4 per cent of this 
is two ounces, which will represent the quantity of solids passed 
daily. 



20 



30 



40 



THE URINE. 



115 



Chemical Constituents. The average composition of a thou- 
sand parts of urine is about as follows : 

Water 950.00 

Urea 26.20 

Kreatine and kreatinine 80 

Urates of sodium and potassium 1.45 

Hippurates of sodium and potassium 70 

Mucus and coloring matters 35 

f Phosphates of sodium and potassium 3.75 

j Phosphates of calcium and magnesium ... .90 



o 



. Chlorides of sodium and potassium 12.55 

»-« |^ Sulphates of sodium and potassium 3.30 

1000.00 
Pathologically there may be present also albumen, glucose, 

blood, bile, etc., besides various sediments. 

Urea — CH 4 N 2 0. This is the most constant and abundant 

organic constituent of the urine, and, being the main nitroge- 




- b 



Fig. 69. {a) Urea ; (b) hexagonal plates ; and (c) smaller scales, or rhombic 
plates of urea nitrate. 

nous excretion of the body, it is the index of nitrogenous waste, 
whether of food or tissue. Its average amount is about one ounce 
per diem. 



116 



THE URINE. 



Urea* crystallizes in colorless prisms, very soluble in water, 
and behaves like an alkaloid, combining readily with nitric and 
oxalic acids to form salts. Both of these salts may be precipi- 
tated in colorless plates from concentrated urine by adding nitric 
or oxalic acid. (Fig. 69, c.) In the course of many diseases it is 
important to estimate the amount of urea excreted day by day. 
A rough estimate may be based on the specific gravity. For, 
since urea is the largest solid ingredient in urine, it follows that 
if sugar be absent, albumen in small amount or removed, and the 
amount of chlorides normal, variations in specific gravity must 
be due mainly to variations in amount of urea. 

The exact methods most generally employed consist in decom- 
posing the urine, by means of chlorinated soda, into nitrogen and 
carbon dioxide, and measuring either the volume of gas evolved 
or the specific gravity lost by the decomposition. 

Davy's Method. A graduated tube closed at one end is one 
third filled with mercury. A measured quantity of the urine (a 
dram or half dram, according to capacity 
of tube) is then added, and the tube is 
next filled to the brim with liquor sod. 
chloratae. Closing the opening with the 
thumb, the tube is inverted over a strong 
solution of common salt in a dish. (Fig. 
70.) The mercury runs out and the salt 
water rises to take its place, while the 
urine and soda mixture, being lighter, 
remain in the upper part of the tube. 
Here the gas from the decomposing urea 
collects. The decomposition is complete 
in three or four hours, when the amount 
of the gas may be read off by the gradu- 
ations upon the tube, every cubic inch 
representing .64 grain (or 1 cubic centi- 
meter representing 2.5 milligrams) of urea. 

Fowler's Method, based on the loss of specific gravity, is easier 
of application. The specific gravity of the urine is carefully de- 
termined as well as that of the liq. sodse chloratse (U. S. P.) to 
be used. One volume of the urine is mixed with exactly seven 
volumes of the liq. sod. chl. and set aside for two hours, or until 




Fig. 70. 



THE URINE. 117 

effervescence ceases. The specific gravity is again taken. As the 
reaction begins immediately on mixing the fluids, the specific 
gravity of the mixture must be calculated. This is done by add- 
ing to the specific gravity of the urine seven times that of the 
liq. sod. chl. and dividing the sum by eight. Each degree of 
difference in specific gravity of the mixture before and after the 
decomposition represents three and a half grains of urea to the 
fluid ounce of the day's urine. 

Example : Ounces. 

Quantity of urine in twenty-four hours 46 

Sp. gr. of the urine 1020 

Sp. gr. liq. sod. chloratae 1042 

(Calculated) Sp. gr. mixture (i^2x7±i_oj2 = ). 1039.2+ 
(Actual) Sp. gr. mixture after reaction 1036.2 

. 1039.2—1036.2=3; 3X3J=10J grs. of urea to the ounce of 
urine; 10JX46— 483 grs. of urea passed in twenty-four hours. 

Kreatine and Creatinine, substances closely allied to urea, exist 
in urine in such small amounts as to be of no practical signifi- 
cance, and need only to be mentioned in this connection. 

Uric Acid is found in the urine of carnivora : in that of her- 
bivora it is largely replaced by an analogous substance — hippuric 
acid. Gout is characterized by an increased production of uric 

Fig. 71. Uric Acid. Fig. 72. Uric Acid. 

acid, and the so-called " chalk -stone" deposit in joints during 
that disease is sodium urate. Free uric acid is so very insoluble 
that whenever it exists in urine it is always a precipitate. It ap- 

I 



118 



THE URINE. 



pears as minute reddish grains, which under the microscope are 
seen to be modifications of rhombic crystals, always stained with 
the coloring matter of the urine. They often deviate widely from 
the typical rhomb, as is shown in Figs. 71 and 72, but an experi- 
enced eye will readily recognize them. Normally, uric acid, as 
soon as formed, unites with the alkaline bases to form urates. 
These are very soluble in warm water, but more sparingly so in 
cold. Therefore a urine, though clear when freshly passed and 

warm, may exhibit a copious 
precipitate upon becoming cold, 
as on a winter night. This pre- 
cipitate is easily recognized by 
its dissolving upon warming. 
Urates of sodium and magne- 
sium generally appear under the 
microscope as amorphous pow- 
ders in moss- like aggregations, 
but occasionally as bundles of 
small needles, as shown in Fig. 
73. The urate of ammonium, a 
result of the alkaline fermenta- 
tion, occurs as opaque, brown 
spherules, smooth or with spiculse like a thorn-apple. (Fig. 67.) 
The acid urates are less soluble than the normal, and often pre- 
cipitate when the urine is very acid or when an acid is added, as 
in the nitric-acid test for albumen. 

The murexid test for uric acid and the urates is- one of great 
beauty. Place some of the sediment in a porcelain dish, add a 
drop or two of nitric acid, and carefully evaporate almost to dry- 
ness. If a few drops of ammonia be added, it assumes a beautiful 
purple color. 

Coloring Matters. Our unsatisfactory knowledge of these 
substances and their clinical significance is to be regretted, since 
some of them possess an importance next to albumen and sugar. 
The existence of at least two distinct substances have been dem- 
onstrated : 

1. Urobilin (urohcematin), derived from the coloring matter of 
the bile, and hence indirectly from the coloring matter of the 
blood. 




Fig. 73. Urates. Oxalate of Calcium. 



THE URINE. 



119 



2. Uro-indican (uroxanthin), a substance closely related to, if 
not identical with, the glucoside indican, and, like that substance, 
it is capable of conversion into indigo-blue. 

To estimate the coloring matters, put some urine in a beaker 
and render it strongly acid with nitric or hydrochloric acid. Let 
it stand six hours for the pigments to be liberated. Then note the 
depth of color by transmitted light. 

Phosphates. The phosphates are derived mainly from the 
food, but to some extent also from oxidation of phosphorized 
tissues : 

1. Earthy Phosphates (Ca and Mg). Being soluble only in 
acid solutions, the earthy phosphates are precipitated when the 
urine is made or becomes alkaline. Furthermore, being less sol- 
uble in warm than cold urine, heat often precipitates them, as in 
the heat test for albumen. Deposits of calcium and magnesium 
phosphates are generally amorphous, and may be distinguished 
from the amorphous urates, (a) by absence of color and not gath- 
ering in mossy forms ; (b) by a 



drop of acetic acid added to the 
sediment on a glass slide un- 
der the microscope — phosphates 
dissolve, while urates gradu- 
ally lose their base and assume 
the characteristic forms of uric 
acid. In ammoniacal urine (al- 
kaline fermentation) the am- 
monio-magnesian phosphate 
(MgNH 4 P0 4 ), the so-called 
triple phosphate, is formed and 
deposited in large prismatic, 
coffin -lid crystals; sometimes, 
also, in ragged stellate or arborescent crystals, resembling those 
of snow. (Fig. 74.) In cases of cystitis this may occur within 
the bladder; hence other calculi often have one or more white 
layers of the mixed phosphates. 

2. Alkaline Phosphates. These constitute the greater portion of 
the phosphates, and are made up mainly of acid sodium phosphate, 
with traces of potassium phosphate. Being very soluble, they 
never form a precipitate. 




Fig. 74. Triple Phosphate. 



120 THE URINE. 

Magnesian Test. The phosphates are best detected and esti- 
mated by precipitation with a solution composed of magnesium 
sulphate, ammonium chloride, and aq. ammonise, each one part, 
and water eight parts. If the precipitate be thick and creamy, 
the phosphates are abnormally increased ; if it be milky, they are 
normal, and if translucent, diminished. 

Chlorides. These consist almost entirely of sodium chloride, 
the quantity depending mainly on what is taken in with the food. 
However, the chlorides are diminished or even disappear from the 
urine in many fevers, especially in pneumonia, much being elimi- 
nated by the sputa. Their reappearance in the urine is often the 
earliest indication of convalescence. Hence their detection and 
estimation are important. 

Silver- Nitrate Test. First add a few drops of nitric acid to pre- 
vent the precipitation of the phosphates. Then, on adding silver 
nitrate solution, only the chlorides will fall as a white precipitate 
of chloride of silver. If the precipitate be in curdy masses the 
chlorides are not diminished ; if only a milkiness be produced, 
they are greatly diminished ; and, if no cloudiness, they are en- 
tirely absent. 

Sulphates. These consist mainly of sodium sulphate, with a 
little of the potassium salt. They are derived principally from 
the food, and in small amount from oxidation of albuminoid sul- 
phurized tissues, especially in fevers. They are detected and 
estimated by precipitation with barium chloride or nitrate, first 
adding a little nitric or hydrochloric acid to hold the phosphates 
in solution. If the precipitate be creamy the sulphates are in- 
creased; if milky, normal, and if translucent, diminished. 

Albumen. Under this head are included various proteid sub- 
stances which, not being osmotic, appear in urine only in patho- 
logical conditions and functional disturbances. Many of the 
specific fevers, as pneumonia, typhoid, and diphtheria, produce 
albuminuria. Albuminous urine is apt to be of diminished trans- 
parency from presence of tube casts, fat granules, epithelial cells, 
etc., and filtering is often necessary before applying the tests. 

Heat Test. A test-tube is one third filled with the suspected 
urine and held in the flame of a spirit lamp, or over the chimney 
of an ordinary lamp, until it boils. If an opacity occurs it must 
be either albumen or earthy phosphates. If earthy phosphates, it 



THE URINE. 



121 



clears up on addition of nitric acid, but if albumen, it is slightly 
increased. 

Nitric-Acid Test. This consists in underlaying the urine with 
nitric acid. Take a test-tube one fourth full, and, holding it 
aslant, gently pour in an equal volume of the acid, allowing it 
to trickle down the inside of the tube and pass beneath the urine. 
Or the acid may be put in first and the urine added afterward. 
An opacity at the junction of the two liquids is either albumen or 
the urates. If urates, it clears up on heating, but if albumen, it 
is permanent. 

Either the heat or nitric-acid test, singly, is unsatisfactory, but 
both performed together are conclusive. However, the following 
sources of error should be borne in mind : (a) If the urine be very 
alkaline and the amount of albumen small, heat will cause no 
opacity; (b) if only a drop or two of nitric acid be added, it may 
hold a small quantity of albumen in solution ; (c) urea may be 
precipitated from a concentrated urine by nitric acid, but heat 
dissolves it; (d) decomposed urates containing ammonium car- 
bonate effervesce on addition of an acid; (e) often after taking 
turpentine, copaiba, etc., nitric acid precipitates resin in yellow- 
ish flakes, redissolved on addition of alcohol. 

Other Tests. Many other substances, as alcohol and certain 
acids and mineral salts, coagulate albumen and are used as tests 
for that substance. But they are less used, less convenient, and 
no more accurate and conclusive than the two already given. 
Among them may be mentioned (a) picric acid, (6) potassio- 
mercuric iodide (KI 50 grs. — HgCl 2 21 grs.), (c) sodium tung- 
state, (d) potassium ferrocyanide. These added in saturated 
solution form white clouds with albumen, provided the urine is 
first acidulated with citric acid, Strips of filter paper steeped 
in these chemicals and dried, or pellets, are sometimes carried 
for use at the bedside. 

Quantitative Estimation. It is often very important that we 
should be able to compare the quantity of albumen in the urine 
from day to day. The accurate method is by precipitation with 
acetic acid and boiling, separation by filtration, drying, and 
weighing by delicate balances, the filter having been previously 
weighed. But as this involves too much time for the busy prac- 
titioner, we must use an approximative method. The easiest way 



122 THE URINE. 

is to precipitate the albumen by heat and nitric acid, set it aside 
for twelve hours or until next visit, and then note the proportion 
of volume occupied by the precipitate — one fourth, one eighth, a 
trace, etc. 

Sugar (Glucose). It has been proven (Dr. Pavy, 1879) that 
healthy urine contains traces of glucose, but quantities of clinical 
significance, and appreciable by the ordinary tests, are present 
only in glycosuria or diabetes, a pathological condition associated 
with some disturbance of the glycogenic function of the liver. 

High specific gravity in a urine pale and copious, suggests 
sugar. Before testing, albumen, if present, should be removed 
by boiling and filtration. 

Fermentation Test Two vials — one for comparison, the other 
for fermentation — are partly filled with the urine. Into one is 
put a bit of baker's yeast about the size of a pea. Both vials are 
loosely plugged with some pervious material, as cotton, and set 
aside where they will keep warm (60° or 70° F.) until next day 
or next visit. If sugar be present, fermentation will occur in the 
vial treated with yeast and C0 2 bubbles up and passes off through 
the cotton plug, and on taking the specific gravity of each, there 
will be a difference due to the loss of sugar in the vial fermented. 

Alkali Test. Boil the urine with liquor potassae or sodse, and 
if glucose be present it will be oxidized and form a molasses-like 
coloration, the depth of which indicates the amount of sugar 
present. On adding nitric acid a molasses-like odor is devel- 
oped and the coloration discharged. 

Alkali- Copper Test. This depends on the power glucose has of 
reducing the cupric to the cuprous oxide. There are several 
methods of performing this test: 

(1) Trommer's. A drop or two of a weak (about 1 to 30) 
solution of cupric sulphate is added to an inch of urine in 
a test-tube, and then an equal bulk of liquor potassse or sodas. 
Immediately there falls, in addition to the earthy phosphates, a 
bluish precipitate. If sugar is present, this precipitate dissolves 
on agitation, forming a blue solution, which, on boiling, depos- 
its a yellow, orange, or red precipitate of cuprous oxide. (See 
p. 79.) 

(2) Fehling's. This differs from Trommer's in the addition of 
tartaric acid or some tartrate to dissolve the blue precipitate. 



THE URINE. 123 

Furthermore, the ingredients are in definite proportion, so as 
to make the solution available for quantitative analysis. Below 
are given the two formulae in general use, one in the French and 
the other in the English measures: 

Fehling's Solution. Pavy's Solution. 

Cupric Sulphate 34.64 grams. 320 grains. 

Potassium Tartrate 173.20 grams. 640 grains. 

Caustic Potash 80.00 grams. 1280 grains. 

Water 1 liter. 20 ounces. 

On standing a long time this solution is apt to spoil, the tar- 
taric acid being converted into racemic acid, which, like glucose, 
will deoxidize the cupric oxide. Hence, it is best to make the 
solution in two separate parts, the cupric sulphate with one half 
the water and the tartrate and caustic potash with the other half. 
For use, mix equal parts, forming Fehling's solution fresh. A 
convenient amount should be put in a test-tube and boiled alone 
for a few seconds. If it remains clear it is good, and the urine 
may then be added gradually. Either immediately, or when the 
heat is reapplied, if sugar be present the reddish precipitate will 
appear. Heat should not be applied longer than a minute, for 
prolonged boiling can cause the reduction of the copper oxide by 
various other organic substances found in urine. 

(3) Haines 1 differs from Fehling's in that glycerine is used 
instead of the tartrate, and the solution does not spoil. 

Alkali- Bismuth Test. (1) To some urine in a test-tube add a 
pinch of bismuth subnitrate and then an equal volume of liquor 
potassse. Boil about two minutes. If sugar be present, the bis- 
muth will be reduced and deposited as a black metallic mirror on 
the sides and bottom of the tube. (2) A bismuth test solution 
corresponding to Fehling's is made by warming a scruple each 
of bismuth subnitrate and tartaric acid in two ounces of water, 
and adding liquor potassae till a clear solution is obtained. This 
boiled with a urine containing glucose gives the black bismuth 
precipitate. 

The elements of the foregoing tests put up in pellets and 
tablets, while more convenient, are less reliable and spoil sooner 
than the solution. 

Picric-Acid Test. This is an extremely delicate test for glu- 
cose, and has the practical advantage of being as good a test for 



124 



THE URINE. 



albumen. To the suspected urine add an equal volume of a sat- 
urated solution of picric acid. A cloudy precipitate indicates 
albumen. Next add a few drops of liquor potassae and warm 
gently. A deep red color indicates sugar, though a lighter colora- 
tion may occur in urine free from glucose. 

Quantitative — (1) Fermentation. Each degree of specific grav- 
ity lost in fermenting represents one grain of sugar to the ounce 
of the twenty-four hours' urine. 

(2) Fehling's. Two hundred minims of the solution is decolorized by 
one grain of sugar.^Two hundred minims (grains) of the test solu- 
tion are measured off into a small flask, 
diluted with twice its bulk of water, and 
gently boiled. (Fig. 75.) A graduated 
burette (also shown in figure) is then 
filled to zero with the urine. To the boil- 
ing test solution the urine is added drop 
by drop till the blue color is discharged. 
By the graduations on the burette the 
quantity of urine added is easily read. 
As that represents one grain of sugar, 
the amount of sugar in the entire urine 
is easily calculated. 

Blood gives to urine a smoky hue, or 
even a dark brown color. Hematuria 
(blood in urine) may occur as the result 
of (a) some disease or injury in the 
genito- urinary tract, as acute nephritis, calculus, parasites, can- 
cer, wounds, etc. ; (b) a depraved condition of the blood, as in 
scurvy, purpura, and eruptive fevers; (c) a disturbance of the 
renal circulation, as in mental emotions, malarial paroxysms, and 
cardiac obstructions. 

If the urine be acid, the blood corpuscles retain their shape 
for several days and are easily recognized by the microscope. They 
appear as amber-colored, biconcave disks, either single or laid 
in rows, like piles of coin. Owing to the biconcavity of the cor- 
puscles their centers and peripheries alternate in brightness and 
shadow, as the object-glass is made to approach or recede. Their 
color and smaller size also serve to distinguish them from pus cor- 
puscles. In doubtful cases a minute drop of blood, taken from 




Fig. 75. 



THE XJRINE. 



125 




Fig. 76. Blood Corpuscles. 



the finger with a needle, may be used for comparison. After 
urine containing blood has stood for some time, the corpuscles lose 
their regular outline and be- 
come shriveled and angular. 
(See a in figure.) If the cor- 
puscles be disintegrated and 
dissolved we must test for blood- 
coloring matters. 

The spectroscope offers the 
best means for their detection, 
but as physicians are seldom 
provided with that instrument, 
the following is the test: Place 
the urine in a test-tube and 
shake up with equal volumes 
of tincture of guiacum and 
ozonized ether or old oil of turpentine. If blood-coloring mat- 
ters are present, the precipitated resin is blue, instead of a dirty 
greenish yellow. 

Bile. Urine containing bile is yellow, froths on shaking, and 
a rag dipped in it and dried is permanently yellow. 

1. Test for Bile - coloring Matters.* Underlay the urine with 
yellow nitric acid or a mixture of nitric and sulphuric acids ; or 
the urine and acid may be placed adjacent on a white plate. In 
either method there occurs, at the junction of the liquids, a play 
of colors, green being prominent and characteristic. 

2. Test for Bile Acids. Add a few grains of cane sugar or 
glucose to the urine and underlay it with sulphuric acid. At the 
junction of the liquid a reddish-purple color appears. As other 
substances than the bile acids may produce this reaction, we must, 
in cases of doubt, evaporate the urine to dryness, extract with 
alcohol, precipitate with ether, and redissolve in distilled water, 
and then apply the test as above. 

Leucin and Tyrosin occur only in bile urine, for they attend 
destructive liver disease, especially acute, yellow atrophy and 



-Bilirubin oxidizes so easily that icteric urine often gives only the green 
coloration, or, if kept long, fails to respond at all. Hence, if fresh icteric urine 
can not be obtained and bile urine must be prepared for demonstration, fresh 
bile from a recently killed animal, and not the inspissated, must be used. 



126 



THE URINE. 




phosphorus -poisoning. They form yellowish crystalline deposits 
(Fig. 77) — leucin as spherules, with concentric striae, and tyrosin 

as sheaf-like bun- 
dles of fine nee- 
dles. 

Calcium Ox- 
alate occurs in 
extremely small 
amounts in nor- 
mal urine, but 
more abundantly 
in the so-called 
oxalic diathesis 
and in certain 
forms of dyspep- 
sia, or after eat- 
ing rhubarb or 
other things con- 
taining it. If per- 
Fig. 77. Leucin Spherules and Tyrosin Needles. sistentlv present 

it may form a (mulberry) calculus. It occurs in both acid and 
alkaline urine, and always as a light delicate precipitate, which 
under high powers is seen to consist of small, brilliant octahedral 
crystals, but sometimes dumb- Fig. 78. 

bells. (Fig. 73.) In certain 
aspects the smaller octahedra 
appear as squares crossed by 
two bright diagonal lines. 

Carbonate of Calcium is 
a very rare deposit in human, 
but abundant in the urine of 
cattle. It occurs in small spher- 
ules, sometimes coalescing; 
acetic acid dissolves it with ef- 
fervescence. 

Hippuric Acid {Horse -uric 
Acid) largely replaces uric acid Carbonate of Calcium. Hippuric Acid. 
in the urine of herbivorous animals, and to some extent in that 
of man, especially after a vegetable diet. It occurs in pointed, 




THE URINE. 



127 



four-sided prisms and acicular crystals, insoluble in acetic acid 
but soluble in alcohol. (Fig. 78.) 

Fat in such quantities as to float on the urine generally comes 
from the introduction of a catheter or from foreign admixture. 




Fig. 79. Fat Globules. 



Fig. SO. Pus Corpuscles. 



Fatty degeneration of kidney, or leakage of a lymph vessel, or 

the opening of an abscess into the urinary tract may cause fat in 

the urine. It occurs as minute, 

highly refracting globules of 

various sizes (see a in Fig. 79), 

but sometimes, especially in 

chylous urine, in more intimate 

emulsion (as at 6), the globules 

appearing under the microscope 

as mere specks. Fat may be 

recognized by its dissolving on 

addition of ether. 

Cyst in is a rare urinary 
sediment, a yellowish deposit of 
hexagonal plates (Fig. 81), not 
dissolved by heat or acetic acid 




Fig. 81. Cystin. 



but readily by ammonia. It is a highly sulphurized body whose 
formation in the system is obscure. It sometimes forms calculi. 
Mucus and Pus. Mucus is a normal constituent of urine. 
It is a transparent fluid, and would be invisible but for the mu- 
cus corpuscles, epithelium, and other sediments entangled in it. 



128 



THE URINE. 



Though closely related to albumen, mucin is coagulated by acetic 
acid and not by heat. Mucus is increased by irritation of the 
urinary tract, but as inflammation supervenes albumen appears 
and the urine is purulent. The mucus and pus corpuscles pre- 
sent the same appearance under the microscope as other leuco- 
cytes, viz., rounded, colorless, very granular cells, a little larger 
than red blood corpuscles. (Fig. 80.) If the urine be greatly di- 
luted, or, better, treated with acetic acid, the cells swell up, lose 
their granular appearance, become transparent, and show their 
nuclei (a in Fig. 80). The pus cell oftener than the mucus cor- 
puscle has more than one nucleus. Pus may be distinguished 
from mucus : (1) It is always attended with albumen ; (2) (Donne's 
test) treated with an alkali it forms a gelatinous mass. 

/ & 




J. d 






Fig. 82. (a) Epithelium from the human urethra ; (&) vagina ; (c) prostate ; 
(d)Cowper's glands; (e) Li ttre's glands; (/) female urethra; (g) bladder. 

Epithelium in the urine may come from any part of the 
genito- urinary tract. The accompanying cut shows the typical 
forms of cells coming from various situations. It is generally 
impossible to locate the origin of an epithelial cell beyond the 
vagina and bladder, for their distinctive differences, but slight at 



THE URINE. 



129 



best, are rendered still fainter by maceration in the urine. Renal 
epithelium comes from the uriniferous tubules, and are rounded 
and granular, and, unlike pus cells, they show their nuclei without 
acetic acid. They are usually associated with albumen and tube 
casts (Fig. 83), and therefore point to kidney disease. 

Tube Casts. In hemorrhage from or inflammation of the 
kidney the urine usually contains microscopic casts or moulds of 
the uriniferous tubules formed by exudation into the tubule of 
coagulable material, which afterward contracts, becomes loose, 
and is washed out with the urine. As they imbed and bring 
away epithelial cells, granular matter, fat globules, blood discs, 
etc., they are a valuable index to the condition of the tubules. 
(1) Epithelial casts (see upper portion of figure) are those bear- 
ing renal epithelium. They indicate desquamative nephritis. 




Fig. 83. Epithelial Cells and Tube Casts. 



Fig. 84. Spermatozoa. 



(2) Hyaline casts (shown in left-hand part of figure) are transparent 
and comparatively free from entangled material. They come from 
tubules whose epithelium is sound and adherent or from those 
bereft of epithelium. In the latter case they are more solid in 
appearance {waxy casts) and indicate serious nephritis. (3) Gran- 
ular casts are opaque from presence of granular debris. (4) Fatty 
casts (see larger cast in figure) are such as carry oil globules, either 
free or contained in epithelial cells. They are proof of fatty 
degeneration of the kidney. (5) Blood casts contain blood cor- 
puscles, and show that the hematuria is of renal origin. 

Spermatozoa occur in urine as a result of spermatorrhea, 



130 



THE URINE. 



nocturnal emissions, or coitus. They are liable to escape observa- 
tion, for they subside slowly, and are very small and transparent. 
Under a high power they are seen to consist of a small oval cell 
with a tail-like prolongation. . Their tadpole-like appearance is 
shown in Fig. 84. They are motionless in urine, and remain for 
days unaltered. 

Micro-organisms. Urine being a solution of organic mat- 
ters becomes as soon as voided a ready medium for the growth 
of the lower forms of life, the germs of which get in from the 
air or unclean vessels. Besides various others we may men- 
tion : (1) Yeast fungus (shown on page 105) is seen during its 
sporule stage as transparent oval cells, sometimes arranging 
themselves in branches. It grows only in saccharine urine, 
though spores closely resembling it are seen in acid urine con- 
taining neither sugar or albumen. (2) Sarcina is a fungus sel- 
dom found in urine but more 
frequently in matters vomited 
during certain diseases of the 
stomach. The cells are arranged 
in cubes, resembling bales 
bound with cross -bands. The 
sarcinse shown at a in figure 




Fig. 85. Sarcina Ventriculi. 



are from the urine, those at b 
from vomited matters. 

1. Bacteria {little rods). This 
is the general term given to 
the minute moving organisms 
invariably present in putrefy- 
ing animal and vegetable mat- 
ter. They consist of simple cells filled with a colorless fluid 
and presenting several varieties of form: (a) Micrococci appear- 
ing as trembling points, distinguished from other particles by 
their progressive motion; (/>) Rods about the length of the di- 
ameter of blood discs, sometimes at rest, but usually vibrating 
across the field; (c) Vibrioses, consisting of several rods joined 
together and moving with greater rapidity; and (d) Zooglea, ag- 
gregations of bacteria held together by gelatinous material and 
resembling masses of amorphous urates or phosphates. These 
various forms are shown in Fig. 67, page 113. Bacteria not only 



THE URINE. 131 

cause decomposition outside, but may set it up in urine while yet 
within the bladder, provided they be introduced from without. 
This may be done by dirty catheters and sounds, or they may 
work . their way down the urethra in the pus of a gleet. The 
ammoniacal fermentation thus set up soon induces cystitis. 

Extraneous bodies, such as hair, wool, or fragments of feathers, 
are often found in urinary deposits, and ludicrous mistakes have 
been made by observers not on their guard for such casual ad- 
mixtures. 

Sediments. The chemical examination of unorganized urinary 
sediments is generally an easy matter, for they usually consist of 
urates, phosphates, calcium oxalate, or uric acid. Warm the sed- 
iment with the supernatant urine, it dissolves — urates. If not, 
warm with acetic acid, it dissolves — phosphates. If not, warm with 
hydrochloric acid, it dissolves — calcium oxalate. If not, it is uric 
acid, which may be confirmed by the murexid test. 

Urinary Calculi. Urinary calculi {calculus, a pebble) are 
composed of urinary sediments which have gathered around some 
nucleus (usually calcium oxalate or uric-acid crystals, or some 
foreign body) within the bladder, and being slowly deposited, par- 
ticle upon particle and layer upon layer, the concretion becomes 
as hard as stone. The concretion often consists of successive 
layers of different sediments deposited during varying conditions 
of the urine. 

The qualitative analysis of calculi is easy. Saw the stone 
through the middle and see whether it be composed of the same 
material throughout or of successive layers of different sediments. 
If the former, take the sawdust; if the latter, chip off a specimen 
from a single layer. But this should be pulverized very fine (for 
it is dissolved much less readily than fresh sediments), and then 
test by means of heat acetic and hydrochloric acids, just as other 
sediments. 

The following method is easier in practice: 

I. Heat to redness on a piece of platinum foil. If no residue, 
see II ; if a residue, see III. 

II. To a fresh portion apply the murexid test. If it responds 
it is ammonium urate or uric acid; it' it does not respond it is 
cyst in or xanthin, see IV. 

III. To the residue, when cool, add hydrochloric acid. If it 



132 THE URINE. 

■ 

effervesces it is an oxalate or urate, which may be determined by 
the murexid test; if it does not effervesce it is & phosphate. 

IV. Dissolve some of the powder in nitric acid. If the solu- 
tion is^yellow it is xanthin; if dark brown it is cystin. 



1 gram = 15.434 grains. 

1 cubic centimeter = 0.061 cubic inch = 0.27 5. 
1 liter = 61 cubic inches = 33.8 §. 
inch. I 



INDEX. 



PAGE. 

Acetanilide, 107 

Acid, acetic, 100 

antinionic, 47 

antimonious, 47 

arsenious, 43 

benzoic, 100 

boric or boraeic, 49 

butyric, 98 

carbazotic, 100 

carbolic, 101 

carbonic, 51 

cathartic, . . 106 

chloric, 27 

chlorous, 27 

chromic, 70 

citric, 101 

cyanic, . 55 

formic, 101 

gallic, 101 

hippuric, 126 

hydriodic, . 25 

hydrobroinic, 25 

hydrochloric, 25 

hydrocyanic, 55 

hydroferricyanie 55 

hydroferrocyanic, 55 

hydrofluoric, 25 

hydrosulphuric, 30 

hypochlorous, 27 I 

hyponitrous, 37 

lilhic (see uric), 117 ' 

malic, 102 

meconic, . 109 

muriatic, 25 

mvronic, 106 

nitric, 39 

nitrohydrochloric, 26, 72 

nitromuriatic, 26, 72 

nitrous, 38 

oleic, 98 

orthophosphoric, 42 

oxalic 102 

palmitic, 98 

perchloric, 27 

phosphoric, 42 

picric, 100 

prussic, 55 

pyrogallic, 102 

pvrophosphoric, 42 

salicylic, 102 

silicic, 56 

sodium phosphate, 119 

stearic, 98 

succinic, 102 

sulphocyanic, 55 



PAGE. 

Acid, sulphovinic, 97 

sulphuric, 33 

sulphurous, 32 

sulphvdric, 30 

tannic, 102 

tartaric, 103 

uric, 117 

valerianic, 103 

Acid salts, 58 

Acids, definition of, 24 

fatty 98 

organic, 100 

Acidulous radicals, 21 

Analytical table, 88 

Afnnitv. chemical, 19 

Air, 35 

Albumen 120 

Alcohol, 94 

amvlic 95 

ethylic 94 

gly eery lie, 96 

mannity] 96 

methylic, 93 

phenylic, 101 

poisoning by, 97? 

radicals, 92 

vinic, 94 

wood 93 

Aldehydes, 99 

Ale, . 95 

Algaroth, powder of, 47 

Alkalies, metals of the 57 

Alkaline earths metals, 62 

Alkaloids, artificial, 107 

liquid, 110 

natural, 108 

of cinchona, 109 

of nux vomica, 109 

of opium, 109 

Alloys, 56 

Allotropic forms, 41, 49 

Aluminium, 67 

bronze, 67 

chloride, 67 

silicates, 68 

sulphate, 67 

Alums, 67 

Amalsrams : ... 56, 80 

Amber, 102 

Amides, 107 

Amines, 107 

Ammonia, 36 

derivatives, 107 

Ammoniac, 92 

Ammoniated mercury, 82 

(133) 



134 



INDEX. 



PAGE. 

Ammonio-chloride of mercury, . 82 

-citrate of iron, 74 

-ferric alum, 68 

-magnesian phosphate, ... 66, 119 

-nitrate of silver, 45 

-sulphate of copper, 45 

-tartrate of iron, 74 

Ammonium, 60 

amalgam, 60 

carbonate, 61, 113 

derivatives, 82 

hydrate, 61 

hydrosulphide, 61 

nitrate, 38 

nitrite, 35 

sulphydrate, 61 

Amygdalin, 55, 106 

Amyl, acetate, 96 

hydrate, 95 

nitrite, 97 

Amylic alcohol, 95 

Amyloses, 103 

Amylum, 104 

Analysis, 16 

acidulous radicals, 87 

definition of, 16 

metallic radicals, 87 

proximate and ultimate, . ... 108 

Aniline, 107 

Antidote, definition of, 44 

Antidotes to acids, . 66 

alkalies, 62 

alkaloids, 109 

antimony, 48 

arsenic, 44 

barium . . 63 

carbolic acid, 101 

copper 80 

cyanides, . 55 

lead, 78 

mercury, 83 

oxalic acid, . . . . 102 

silver, 85 

sulphuric acid, 34 

Anjifebrin, 107 

Antimonious chloride, 47 

hydride, 47 

oxychloride, 47 

oxide, 47 

sulphide, 48 

Antimoniuretted hydrogen, ... 47 

Antimony, . . 47 

Antimony and potassium tartrate, 47 

Antimonyl, 47 

Antipyrine, 108 

Antiseptics, 36 

Antizymotics, 36 

Babbitt's metal, 47 

Bacteria, 130 

Baking powders, 59 

Balsams, 92 

Barium, 63 

Barium chromate, 67 

Basylous radicals, 21 

Beer, 95 

Beet sugar, . . . 104 

Bengal light, 63 



PAGE. 

Benzine, 91 

Benzoin, 92 

Bichromates, 70 

Bile in urine, 125 

Bilirubin, 125 

Bismuth, ' 18 

ammonio-citrate, 48 

nitrate, 48 

oxynitrate, 48 

subcarbonate, . . 48 

subnitrate, 48 

Bismuthyl, 47 

Black lead, 49 

Black oxide of manganese, ... 71 

Bleaching, 18, 23, 32, 65 

Bleaching powder, 64 

Blood casts, . 129 

Blood in urine, 124 

Blue ointment, 81 

Blue pill, . . 81 

Bluestone, 79 

Blue vitriol, 79 

Boroglyceride, 49 

Boron, 49, 67 

Brandy, 95 

Brass, 68 

Brimstone, 29 

Britannia, 47 

British gum, 104 

Bromides, tests for, 26 

Bromine, . . 22 

Bromum, 22 

Bronze, aluminium, 67 

Butter of antimonv, 47 

Butyl, 93 

Cadmium, 69 

Ciesium, 57 

Calcium, 63 

carbonate, 63, 126 

chloride, 63 

hydrate, . 64 

oxalate, 65, 126 

oxide, 64 

phosphate, ............ 65 

sulphate, 65 

Calculi, urinarv, 131 

Calomel, . . ." • . . 82 

Calx, 64 

Calx chlorata, 64 

Camphor, monobromated, .... 92 

Camphors, 92 

Cane sugar, 104 

Caoutchouc, 92 

Caramel, 95 

Carbohydrates, 10:5 

Carbon, 49 

dioxide, 51 

disulphide, 31 

monoxide, 51 

Catalysis, 12, 20, 97 

Caustic ammonia, ........ 61 

Caustic potash, 59 

Cellulin, 103 

Celluloid, 103 

Cellulose, 103 

Centimeter, cubic, 132 

Cerium, 68 



INDEX. 



135 



PAGE. 

Chalk, 63 

Charcoal, 50 

Chemical action 5 

Chemical affinity, 19 

philosophy, , 5, 18 

Chemistry, definition of 5 

inorganic, 10 

organic, . . 90 

Chinoline, 108 

Choke damp, 51 

Chloral, 99 

Chloralum 67 

Chloride of lime, 64 

Chlorides in nrine, 120 

Chlorides, tests for, 26 

Chlorinated lime, 64 

Chlorine, 22 

Chlorine oxides, 27 

Chloroform, ' . . 98 

Chromates, 70 

Chrome yellow, 77 

Chromium, 70 

Chromium trioxide, 70 

Cider, 95 

Cinchona alkaloids, 109 

Cinchonicine, 109 

Cinchonidine, 109 

Cinchonine, ." 109 

Cinnabar 83 

Citrine ointment, 81 

Classification of elements, .... 10 

Clay 56 

Coal. 50 

Cobalt, 75 

Cocaine, 110 

Codeine, 109 

Coin, 84, 85 

Collodion 104 

Colocynthin, 106 

Cologne, 92 

Coloring matters, urinary, . . .118 

Combining weights, . 8 

Combustion, . . 13 

Compounds, 6 

Conine, 110 

Copper, ammonio-sulphate, . .' . 45 

black oxide, 79 

group, . 78 

• suboxide, 79 

Copperas, 73 

Corrosive sublimate, 82 

Cotton, 103 

Creasote 101 

Greta prepa.rata , 63 

Crystallization, water of 16 

Cupric hydrate, 79 

oxide, " 79 

subacetate, 79 

sulphate, 79 

Cyanates, 55 

Cyanides, compound 55 

Cyanogen, 54 

Cystin, 127 

Decantation, 59, 64 

Decay, 106 

Deflagrating spoon, 13 

Deliquescent, 16 



PAGE. 

Deodorizers, 36 

Deposits, urinarv, 131 

Dextrin, 104 

Diabetic urine, 122 

Dialyzed iron, 73 

Dialysis, 73 

Diamond, 49 

Diastase, 105 

Didymium, 67 

Diffusion, 53 

Digitalin, 106 

Disinfectants, 23 

Disinfectants, 36 

Distillation, 17 

Donne's test 128 

Donovan's solution 43 

Draught in rooms, ....... 54 

Drummond light, 12 

Dynamite, 96 

Earths, metals of the, 67 

Earthy phosphates, 112, 119 

Effervescence, 52 

Efflorescent, 16 

Elaterin, 107 

Electrolysis 18 

Electro positive and negative, . . 18 

Elements, 7 

classification of. 10 

Emplastrum plvmbi 76 

Epithelial casts 129 

Epithelium, 128 

Epsom salts, 66 

Equations, 9 

Erbium 67 

Essential oils, 91 

Etching 26 

Ether, 96 

chloric, 97 

hydrobromic 97 

hydrochloric, 97 

nitrous, 97 

ozonized, 125 

sulphuric, 96 

Ethers, compound, 93, 96 

simple, 93, 96 

Ethyl bromide, 97 

chloride, ... 97 

hydrate, 94 

nitrate, 97 

oxide, 96 

Ethylic alcohol, 94 

Evaporation, 6 

Extraneous bodies in urine, ... 131 

Patty casts, 129 

Fats! 98, 127 

Feb ling's test, 122 

Fermentation acid. 113 

alkaline, 113 

Ferments, 105 

Ferri eitras, 74 

ft ammonii eitras, 74 

et ammonii tartras, 74 

etpofa*$ii tartras, 74 

et quiniae eitras, 74 

et strichnix eitras, 74 

pyrophosphas, 74 

Ferric chloride, 72 



136 



INDEX. 



PAGE. 

Ferric hydrate, 73 

nitrate, 74 

sulphate, 73 

Ferricyanogen, 55 

Ferrocyanogen, 55 

Ferritin redactum, 72 

Ferrous chloride, 72 

hydrate, 73 

iodide, 74 

sulphate, 73 

sulphide 74 

Filtration, 64 

Fixed oils, 98 

Flint, 56 

Flowers of sulphur, 29 

Fluorides, tests for, 26 

Fluorine, 22 

Fluorspar,. . 22 

Fluxes, 72 

Flystone, 75 

Formulae, 9 

Fowler's solution, 43 

Fractional distillation, ...... 17 

Fruit essences, artificial, 96 

Fungi, 112 

Fusel oil, 95 

Galena, 76 

Galls, oak, 102 

Galvanized iron, 68 

Gas, definition of, 6 

Gas, illuminating, 51 

German silver, 75 

Glass, 56 

Glucose, 105, 122 

Glucosides, 106 

Glycerine, 96 

Glycerrhizin, 107 

Glyceryl hydrate, 96 

Glycerylic alcohol, 96 

Glvcogen, 104 

Gold, 85 

Goulard's extract, 77 

Gram, 132 

Granular casts, 129 

Grape sugar, 105 

Graphite, 49 

Gravity, specific, 6 

Gray powder, 80 

Green fire, 63 

Green vitriol, 73 

Guiacum, tincture, 125 

Gum resins, 92 

Gams, 104 

Gun cotton, 103 

Gutta-percha, 92 

Gypsum, 65 

Haines' test, 123 

Hard water, 16, 65 

Hartshorn, 37 

Homologous series, 91 

Hyaline casts, 129 

Hydracids, 25 

Hydrargyri — 

chloridum mite 82 

cum creta, 80 

iodidum rubrum, 81 

iodidum viride, 81 



PAGE. 

Hydrargyri— 

oxidum rubrum, 82 

oxidum flavum, 82 

subsulphas flavus, 82 

Hydrargyrum, 78 

Hydrobromic ether, 97 

Hydrocarbons, 91 

Hydrochloric ether, ....... 97 

Hydrogen, 11 

dioxide, 18 

oxide, 15 

peroxide, 15 

sulphide, 30 

"Hypo-" 27 

Hvposulphites, 32 

"-Ide," 25 

"-Ic," 20, 27 

Ignis fatuus, 41 

India rubber, 92 

Indican, .' 107, 119 

Ink, black, 102 

indelible, 85 

sympathetic, 75 

Insolubility, influence of, ... . 20 

Insoluble chlorides, 84 

Introduction, 5 

Iodide of starch, 25 

Iodine, 22 

Iodides, tests for, 26 

Iridium, 86 

Iodoform, 98 

Iron, 71 

by hydrogen, 72 

group, 70 

reduced, 72 

salts (see ferrous and ferric), . . 71 

scale compounds of, 74 

Isomerism, 91, 103 

"-Ite," 27 

Jalapin, 107 

Javelle water, . 60 

Kalium, 57 

Kaolin, 68 

Kerosene, 91 

Kreatine, 117 

Kreatinine, 117 

Labarraque's solution, 60 

Lana philosophica, 69 

Lanthanum, 67 

Laughing gas, 38 

Lac sulphuris, 29 

Lead, 76 

acetate, 76 

carbonate 77 

chloride, 77 

chromate, 77 

group, 75 

oxide, 76 

plaster, 76 

puce, 76 

red, 76 

subacetate, 77 

sugar of, 76 

sulphate, 77 

sulphide, 77 

water, 77 

white, 77 



INDEX. 



131 



PAGE. 

Leucin, 125 

Lignin, 108 

Lime (see calcium) 64 

kilns, 64 

water 64 

Limestone, 63 

Limestone, magnesian 65 

Linen, 108 

Linseed oil 99 

Liquid, definition of 6 

Liquor aeidi arseniosi 43 

. arsenii et hydrargyri iodidi, . . . 43 

cal^is G4 

definition of .... 61, 75 

Jerri chloridi, 73 

Jerri nit rat is, 74 

Jerri tersulphat is, < :; 

hydrargyri nit rat is, 81 

iodi compositus 24 

magnesii citratis, (><o 

potassx 57 

potassii arscnitis 43 

pluinbi subacetatis. ../.... 77 

subsulphatis, 73 

Liter, 132 

Litharge, 76 

Lithium 62 

Litmus 24, 62 

Lixiviation. . .■ "^ s 

Lubricating oil, 91 

Lugol's solution 24 

Lunar caustic v 4 

Luster, metallic 56 

Lye 58 

Magnesia 66 

Magnesian fluid, 42. 120 

Magnesian limestone 65 

Magnesium 65 

carbonate 66 

citrate 66 

hydrate. 66 

oxide 66 

sulphate, 66 



Malt. 



105 



Manganates, . 71 

Manganese, 71 

dioxide 12, 22. 71 

Manganous sulphate 71 

sulphide, 71 

Manna, 96 

Mannite 96 

Mannityl alcohol, ......... 96 

Marble 63 

Marsh's test 46 

Matter. ..'... 5 

Measures 132 

Meerschaum 65 

Menthol 92 

Mercurial ointment 81 

Mercuric ammonium chloride . . s 2 

chloride 82 

cvanide 54 

nitrate 81 

oxide 

sulphide 83 

Mercurous chloride 82 

iodide, 81 



PAGE. 

Mercurous nitrate 

oxide s - 

sulphate, s l 

sulphide, 

Mercury v " 

acid nitrate s l 

ammoniated, 

bichloride, 

biniodide s l 

black oxide. 82 

green iodide v l 

mild chloride, 

oleate 

proto-iodide 81 

red iodide, - s l 

red oxide, : . . v - 

vellow oxide v - 

Metals. . 10,56 

Methyl hydrate 98 

Methylated spirit 94 

Methylic alcohol 93 

Metric measures 132 

Micoderma aceti, 100. 105 

Micrococci 130 

Micro-organisms 130 

Milk of magnesia 66 

Milk of sulphur, 29 

Milk sugar 105 

Millimeter 132 

Molecules. 8 

Monobromated camphor 92 

Monsel's solution 3 

Morphine 109 

Mother of vinegar, 106 

Mucilage of starch, 104 

Mucus 112. 127 

Mulberry calculus 126 

Murexid test, 118 

Myrrh 92 

Naphtha 91 

Narcotine, . . 109 

Nascent state, 20 

Natrium, 57. 60 

Negative radicals 21 

Neutralization, 61 

Nickle 75 

Nicotine 110 

Nitrates, test for 40 

Nitric oxide 38 

Nitrite of aniyl 97 

Nitrites 38 

Nitro-cellulose. 103 

Nitrogen. 34 

dioxide 38 

hydride 36 

monoxide, ;:;s 

oxides 37 

pentoxide 39 

tetroxide, 39 

trioxide 38 

Nitrogenous bodies 107 

Nitro-glycerine, 96 

Nitrous ether, 97 

Nitrous oxide 38 

Non-metals 10, 11 

Nux-vomica alkaloids, 109 

Oidium albicans. 106 



138 



INDEX. 



PAGE. 

Oil, fusel, 95 

Oil of vitriol, 33 

Oils, essential, 91 

fixed, 98, 127 

volatile, 91 

Oleo-resins, 92 

Oleum terebinthinx, 92 

Opium alkaloids, 109 

Organic chemistry, 90 

Organized bodies* 90 

Orpiment, . . 43 

"-Ous," 20, 27 

Oxacids, 25 

Oxalate of lime, 65, 126 

Oxidation, 13 

Oxide, definition of, 13 

Oxidizing agents 13 

Oxygen, 12 

Oxygenated water, 13 

Oxyhydrogen flame, 12 

Ozone, ' 14 

Ozonized ether, 125 

Painters' colic, 78 

Pancreatin, 105 

Paper 103 

Paraffine, 91 

Paraldehyde, 99 

Parchment, artificial, 103 

Paris green, 45 

Pearl ash, 58 

Pearl white, 48 

Pepsin, 105 

"Per-" 27 

Peru, balsam of 92 

Petroleum, 91 

Pewter, 48, 76 

Phenol, 101 

Phenyl alcohol, 101 

Phenyl amine 107 

Phosphates in urine, 119 

Phosphine, 41 

Phosphoretted hydrogen, .... 41 

Phosphorus, . 40 

hydride, 41 

oxides, 41 

pentoxide, 42 

Pilula hydrargyri, 81 

Plaster of Paris 65 

Platinic chloride, 60, 86 

Platinum, 86 

Plumbago, 19. 

Plumbum, 76 

Poisoning by chloroform 98 

Porcelain, 68 

Porter, 95 

Port wine, 95 

Potassium, 57 

acid carbonate, 58 

bromide, 59 

bicarbonate, 58 

bichromate, 70 

bitartrate, 58 

carbonate, 58 

chlorate, 12, 28 

chromate, 70 

ferricyanide, 55 

ferrocyanide, 55 



Potassium— page. 

hydrate, 59 

hypochlorite, 59 

iodate, 59 

manganate, 71 

permanganate, 71 

red chromate, 70 

sodium tartrate, 59 

sulpho-cyanate, 55 

Potato starch, 104 

Powd-er of Algaroth, 47 

Precedence of affinities, 19 

Precipitated chalk. . 63 

Principles, proximate and ulti- 
mate 108 

Propylamine 107 

Propyl, 93 

Proximate analysis, 108 

principles 108 

Prussiate of potash, red, 55 

yellow, 55 

Ptomaines, 110 

Ptyalin, 105 

Ptyalism, 83 

Pus in urine, 112, 127 

Putrefaction, 106 

Pyroligneous spirit, 93 

Quevenne's iron, 72 

Quick lime, 64 

Quicksilver, 80 

Quinicine 109 

Quinidine, 109 

Quinine, 109 

Quinoidine, 109 

Radicals, definition of, 18 

basylous, 21 

negative, 21 

positive, 21 

the alcohol, 92 

Rancidity of fats, 99 

Ratsbane, 43 

Realgar, . 43 

Red fire, , . 63 

Red prussiate of potash, 55 

Reduced iron, 72 

Reinsch's test, 45 

Resina, 92 

Resins, 92 

Resorcin, 101 

Respiration 13 

Rochelle salt, 59 

Rock crystal, 56 

Roll sulphur, , 29 

Rosin (see resin), 92 

Rubidium, 57 

Saccharoses, 104 

Salivation, 83 

Salt, common, 25 

Sal volatile, 61 

Samarium, . 67 

Sand, 56 

Santonin, 107 

Sarcina, 130 

Saturnine, colic, 78 

Saturnum, 76 

Scale compounds of iron, .... 74 

Scandium, . . 67 

Scheele's green, 45 



INDEX. 



139 



PAGE. 

Sediments, urinary. 131 

Selenium, 28 

Sewer gas, 30 

Sherry wine, 95 

Silicic oxide, 56 

Silicon, 

Silver, action of light on 85 

ammonio-nitrate, 45 

arsenite, 45 

bromide, ^4 

chloride. v 4 

cyanide, B4 

iodide, 84 

nitrate, v 4 

oxide, 84 

german, 

group, 84 

Slaked lime 64 

Soaps, * 65, 99 

Soapstone, 

Soda-water, ~>2 

Sodio-ammonium 60 

Sodio-potassium tartrate, .... 59 

Sodium, 60 

hypochlorite, 60 

hvposulphite, 32 

salicylate, 102 

Solid, definition of 6 

Soluble glass 56 

Solution, nature of, 15 

Specific gravity, 6 

Spectroscope, . • 125 

Spermatozoa, 129 

Spirit, methylated, 

pvroligneous 98 

Spirits 

of wine 

Spiritus astheris nitrosi, 97 

ammonue, 61 

frumcnti, 95 

vlni gallici, 95 

Stannic salts 76 

Stannous salts, 76 

Stannum 75 

Starch, ■ 104 

Steel, 72 

Stereotyping metal 18 

Stibine, 47 

Stibium 17 

Strontium 

Strychnine. 109 

Styptic collodion 101 

Sublimation. 17, 15 

Sublimed sulphur, 29 

Sucrose, 104 

Sugar, beet 104 

cane 101 

diabetic, 105, 122 

grape 105, 122 

in urine 122 

milk, 105 

of lead 76 

Sulphates, tests for 34 

Sulphites, 32 

Sulphocyanates, 55 

Sulphur, 28 

dioxide 32 



PANE. 

Sulphur latum 29 

precipitatum, 2'J 

sublimatuiit, 29 

trioxide 32 

Sulphuretted hydrogen 30 

Sulphuric ether, 96 

Supporter of combustion 13 

Symbols 

Svnthesis 16 

Syrupus caleii laetophosphatis, . . . 65 

scilht comp., 17 

simplex, 105 

Table, analytical, for metals, ... 

analytical, for neg. radicals. . . 88 

of elements 

of solubilities, 

of valences 21 

Tannin 102 

Tartar, cream of, 5^ 

emetic, 47 

Tellurium, 

Temperature, influence of 19 

Terebene 92 

Tersulphate of iron, 73 

Tests, acidity 24 

acidulous radicals 

alcohol, V'l 

alkali metals, 62 

alkaline earth metals 6*3 

alkalinity 61 

ammonia, 37 

ammonium salts, 62 

antimony. 4^ 

arsenic. 

barium, 63 

bile, 

bismuth 

blood 125 

boron 49 

bromides 26 

bromine 21 

brucine. 109 

cadmium 69 

calcium, 67 

carbonates, 52 

carbon dioxide, 52 

chlorides, 12. 26 

chlorine, 21 

chloroform, 

cobalt .5 

coloring matters, urinary. . . . 119 

copper," * . . . . 79 

cvanides 55 

fats, 127 

fluorides. 26 

fluorine, 21 

gallic acid, 101 

hard water 16 

hydrocyanic acid, 55 

hydrogen sulphide 31 

iodides 26 

iodine, 21 

iron, 75 

lead, 7^ 

lithium i'.2 

magnesium. 67 

manganese, 71 



140 



INDEX. 



PAGE. 

Tests, Marsh's, 46 

meconic acid, 109 

mercury, 83 

metallic radicals, 87 

morphine, 109 

nickel, 75 

nitrates, 40 

nitric acid, 40 

organic matter in water, ... 17 

oxalic acid, 102 

oxygen, 13, 38 

ozone, . . 14 

phosphates, 120 

phosphorus, 41 

potassium, 60 

pus, 18,128 

pyrogallic acid, 102 

quinine, 109 

Reinsch's, 45 

salicylic acid, -102 

silver, 85 

sodium, 60 

strychnine, 109 

strontium, 63 

sugar, 122 

sulphates, 34, 121 

sulphuric acid, 34 

tannic acid 102 

urates, ... 118 

urea, 116 

uric acid, 118 

urinary calculi, 131 

urinary sediments, 131 

water in alcoho], 79 

zinc, 69 

Thrush, 106 

Tin, 75 

Tinct. Jerri chloridi, 73 

iodl, 24 

Tinctures, 61, 94 

Tolu, 92 

Toxicology of arsenic, 43 

Trichloraldehyde, 99 

Trichlorm ethane, 98 

Trimethylamine, 107 

Triple phosphate, 119 

Trommer's test, 122 

Tube casts, 129 

Turpentine, 92 

Turpeth mineral, 82 

Type metal, 47 

Tyrosin, 125 

Ultimate analysis, 108 

principles, 108 

Unguentum hydrargyria 81 

nitratis, 81 

Urates, 112, 118 

Urea, 108, 115 

nitrate, 115 

quantitative analysis, 116 

Uric acid, 117 

Urinary calculi, 131 

sediments, 131 

Urine, Ill 

acid fermentation, 113 

alkaline fermentation, 113 

chemical constituents, 115 



PAGE. 

Urine, color, 112 

coloring matters, 118 

fluidity, 112 

normal, Ill 

odor, 112 

opacity, 112 

quantity, Ill 

reaction, 113 

specific gravity, ..114 

transparency, Ill 

Urinometer, 114 

Urobilin, 118 

Urohsematin, 118 

Uroindican, 119 

Uroxanthin, 119 

Valence, 20 

Valerian, 103 

Vaseline, 91 

Ventilation, 52 

Verdigris, 79 

Vermilion, 83 

Vibriones, 130 

Vinegar, 100 

Vinumrubrum, .• 95 

Xericum, 95 

Vitriol blue, 79 

green, 73 

oil of, 33 

white, 69 

Volatile oils, . 91 

Volatility, influence of, 19 

Vulcanized rubber, 92 

Water, 15 

hard, 16, 65 

impure 16 

mineral, 16 

natural, 16 

of crystallization, 16 

oxygenated, 18 

Waxy casts, 129 

Weights, atomic, 8 

combining, 8 

specific, 6 

White arsenic, 43 

lead, 77 

precipitate, 82 

vitriol, 69 

Whisky, 95 

"Will b' the wisp," 41 

Wines, 95 

Wood alcohol, 93 

naptha, ■. . . 93 

spirit, 93 

Woodv fiber, 103 

Xantliin, 131 

Yeast fungus, 105, 130 

Yellow prussia te of potash, ... 55 

Ytterbium, 67 

Yttrium, 67 

Zinc, 68 

carbonate, 69 

chloride, 69 

oxide, 69 

sulphate, 69 

sulphide, 69 

white 69 

Zooglese, 130 



